Power source with wide output voltage range

Abstract

The present application relates to the technical field of power source circuits. Disclosed is a power source with a wide output voltage range. The power source comprises: an external power source detection circuit, a first voltage generation circuit and a second voltage generation circuit, wherein the external power supply detection circuit is powered by the control power supply; the first voltage generation circuit is used for outputting, when the external power source meets power supply requirements, a voltage corresponding to the external power supply; and the second voltage generation circuit is used for converting an input power source when the external power supply does not meet the power supply requirements, and outputting a converted voltage. The present application can control different voltage generation circuits to supply power to the outside, and an external power source meeting the power supply requirements can work in a relatively wide voltage range, so that the power source can have a relatively wide output voltage range. Moreover, when a first voltage generation circuit works, the power consumption of the external power source is consumed, such that the power consumption of the power source with a wide output voltage range can be greatly reduced.

Description

A power supply with a wide output voltage range

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 6, 2024, with application number 202410167068.2 and invention name “A chip internal power supply circuit with multi-voltage input”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of power supply circuits, and in particular to a power supply with a wide output voltage range. Background Art

[0003] A switching power supply circuit generally includes a power circuit and an integrated circuit control chip. The supply voltage or reference voltage of each module inside the integrated circuit control chip is generally directly generated by the power supply inside the chip.

[0004] However, traditional chip internal power supplies can usually only generate a fixed output voltage. When the integrated circuit control chip is used in switching power supply circuits in different application scenarios, each module inside the chip requires a different supply voltage or reference voltage, resulting in the integrated circuit control chip internal power supply being unable to be used in switching power supply circuits in multiple scenarios. Summary of the Invention

[0005] In view of this, the present application provides a power supply with a wide output voltage range to solve the problem that the voltage generating circuit cannot be applied to multiple scenarios.

[0006] In a first aspect, the present application provides a power supply with a wide output voltage range, comprising: an external power supply detection circuit, a first voltage generating circuit, and a second voltage generating circuit;

[0007] The external power detection circuit is powered by a control power supply; the output end of the external power detection circuit is connected to the input ends of the first voltage generating circuit and the second voltage generating circuit;

[0008] The external power detection circuit is configured to detect whether the external power supply meets the power supply requirements; if the external power supply meets the power supply requirements, the output end of the external power detection circuit outputs a first control signal; if the external power supply does not meet the power supply requirements, the output end of the external power detection circuit outputs a second control signal;

[0009] The first voltage generating circuit is configured to: output a voltage corresponding to the external power source in response to the first control signal;

[0010] The second voltage generating circuit is configured to: convert the input power supply in response to the second control signal and output the converted voltage;

[0011] The external power supply detection circuit includes: a current source B1, a first switch tube M1, a second switch tube M2, a third switch tube M3, a fourth switch tube M4, a fifth switch tube M5, a sixth switch tube M6, a seventh switch tube M7, an eighth switch tube M8, a ninth switch tube M9, a tenth switch tube M10, a first resistor R1, a second resistor R2, and a first inverter A1; wherein the first switch tube M1, the second switch tube M2, the seventh switch tube M7, the eighth switch tube M8, the ninth switch tube M9, and the tenth switch tube M10 are NPN-type transistors or N-type field-effect transistors; and the third switch tube M3, the fourth switch tube M4, the fifth switch tube M5, and the sixth switch tube M6 are PNP-type transistors or P-type field-effect transistors.

[0012] The input end of the current source B1 is configured to be connected to the control power supply, and the output end of the current source B1 is connected to the current input end of the first switch tube M1;

[0013] The control end of the first switch tube M1 and the control end of the second switch tube M2 are both connected to the current input end of the first switch tube M1; the current output end of the first switch tube M1 and the current output end of the second switch tube M2 are grounded;

[0014] One end of the first resistor R1 is configured to be connected to the external power supply, and the other end is grounded through the second resistor R2;

[0015] The current input ends of the third switch tube M3, the fourth switch tube M4, the fifth switch tube M5, and the sixth switch tube M6 are all configured to be connected to the control power supply;

[0016] The control end of the third switch tube M3 and the control end of the fourth switch tube M4 are both connected to the current output end of the fourth switch tube M4; the current output end of the third switch tube M3 is connected to the current input end of the ninth switch tube M9, and the current output end of the fourth switch tube M4 is connected to the current input end of the seventh switch tube M7;

[0017] The control end of the fifth switch tube M5 and the control end of the sixth switch tube M6 are both connected to the current output end of the fifth switch tube M5; the current output end of the fifth switch tube M5 is connected to the current input end of the eighth switch tube M8, the current output end of the sixth switch tube M6 is connected to the current input end of the tenth switch tube M10, and is also connected to the input end of the first inverter A1; the output end of the first inverter A1 serves as the output end of the external power detection circuit (100);

[0018] The control terminal of the seventh switch tube M7 is configured to be connected to the first reference voltage, and the control terminal of the eighth switch tube M8 is connected to the end of the first resistor R1 close to the second resistor R2; the current output terminal of the seventh switch tube M7 and the current output terminal of the eighth switch tube M8 are both connected to the current input terminal of the second switch tube M2;

[0019] The control end of the ninth switch tube M9 and the control end of the tenth switch tube M10 are both connected to the current input end of the ninth switch tube M9 ; the current output end of the ninth switch tube M9 and the current output end of the tenth switch tube M10 are grounded.

[0020] In a second aspect, the present application provides a semiconductor integrated circuit control chip, comprising the power supply with a wide output voltage range as described in the first aspect above.

[0021] In a third aspect, the present application provides a switching power supply circuit, comprising the semiconductor integrated circuit control chip described in the second aspect above.

[0022] The present application can control different voltage generation circuits to supply power to the outside, and an external power supply that meets the power supply requirements can operate within a wide voltage range, allowing the power supply to have a wide output voltage range. Furthermore, the first voltage generation circuit is powered by the external power supply. When the first voltage generation circuit is operating, it consumes the power of the external power supply, thereby significantly reducing the power consumption of the power supply with a wide output voltage range, placing the power supply with a wide output voltage range in a low-power state and ensuring low overall power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of this application or the technical solutions in related technologies, the following is a brief introduction to the drawings required for use in the specific implementation methods or related technical descriptions. Obviously, the drawings described below are some implementation methods of this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0024] FIG1 is a schematic structural diagram of a power supply with a wide output voltage range according to an embodiment of the present application;

[0025] FIG2 is a first structural diagram of an external power detection circuit according to an embodiment of the present application;

[0026] FIG3 is a second structural diagram of an external power supply detection circuit according to an embodiment of the present application;

[0027] FIG4 is a schematic structural diagram of a first voltage generating circuit according to an embodiment of the present application;

[0028] FIG5 is a first structural diagram of a second voltage generating circuit according to an embodiment of the present application;

[0029] FIG6 is a second structural diagram of a second voltage generating circuit according to an embodiment of the present application;

[0030] FIG7 is a schematic diagram of a circuit structure of a power supply with a wide output voltage range according to an embodiment of the present application.

[0031] Explanation of the accompanying symbols: 100, external power supply detection circuit; 200, first voltage generating circuit; 300, second voltage generating circuit; 101, first hysteresis circuit; 102, second hysteresis circuit; 201, response circuit; 202, switch circuit; B1, current source; M1, first switch tube; M2, second switch tube; M3, third switch tube; M4, fourth switch tube; M5, fifth switch tube; M6, sixth switch tube; M7, seventh switch tube; M8, eighth switch tube; M9, ninth switch tube; M10, tenth switch tube; M11, eleventh switch tube; M12, twelfth switch tube; M13, thirteenth switch tube; M14, fourteenth switch tube; M15, fifteenth switch tube; M16, sixteenth switch tube; M17, seventeenth switch tube; M19, nineteenth switch tube; M20, twentieth switch tube Gate tube; M21, the twenty-first switch tube; M22, the twenty-second switch tube; M23, the twenty-third switch tube; M24, the twenty-fourth switch tube; M25, the twenty-fifth switch tube; M26, the twenty-sixth switch tube; M27, the twenty-seventh switch tube; M28, the twenty-eighth switch tube; M29, the twenty-ninth switch tube; M30, the thirtieth switch tube; M0, the power supply switch tube; R1, the first resistor; R2, the second resistor; R3, the third resistor; R4, the fourth resistor; R5, the fifth resistor; R6, the sixth resistor; A1, the first inverter; A2, the second inverter; A3, the third inverter; A4, the fourth inverter; Z1, the voltage regulator diode. DETAILED DESCRIPTION

[0032] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0033] In the description of this application, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be understood to indicate or imply relative importance. Unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, removable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0034] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0035] In this embodiment, a power supply with a wide output voltage range is provided. Referring to FIG. 1 , the power supply includes an external power detection circuit 100 , a first voltage generating circuit 200 , and a second voltage generating circuit 300 .

[0036] The external power detection circuit 100 is powered by a control power supply VDD; an output terminal of the external power detection circuit 100 is connected to input terminals of the first voltage generating circuit 200 and the second voltage generating circuit 300 .

[0037] The external power supply detection circuit 100 is configured to detect whether the external power supply EVIN meets the power supply requirements; when the external power supply EVIN meets the power supply requirements, the output end of the external power supply detection circuit 100 outputs a first control signal; when the external power supply EVIN does not meet the power supply requirements, the output end of the external power supply detection circuit 100 outputs a second control signal.

[0038] Furthermore, the first voltage generating circuit 200 is configured to: output a voltage VOUT corresponding to the external power supply EVIN in response to a first control signal; the second voltage generating circuit 300 is configured to: convert the input power supply VIN in response to a second control signal, and output the converted voltage VOUT.

[0039] In this embodiment, the power supply is divided into different circuits and is powered by different power supplies. As shown in Figure 1, the external power detection circuit 100 is powered by the control power supply VDD, and the second voltage generation circuit 300 is powered by the power supply VIN. The external power detection circuit 100 mainly generates a control signal and can be powered by the control power supply VDD. For example, the control power supply VDD can be a low-voltage power supply. The second voltage generation circuit 300 needs to output a certain voltage VOUT to the outside to power other circuits, such as providing a power supply voltage or a reference voltage to the internal modules of the chip. The second voltage generation circuit 300 can be powered by the power supply VIN. For example, the power supply VIN has a higher voltage than the control power supply VDD.

[0040] For example, when the chip is operating, it needs to be provided with a corresponding power supply. In this embodiment, this power supply can be used as the power supply VIN, which is also the power supply for the chip. In addition, a low-power voltage source can be generated within the chip, and this low-power voltage source can be used as the control power supply VDD. Furthermore, when the low-power voltage source is a low-power, low-voltage source, by providing a relatively low control power supply VDD to the external power detection circuit 100, the external power detection circuit 100 can operate in a low-voltage scenario, effectively reducing the power consumption of the external power detection circuit 100.

[0041] Furthermore, the first voltage generating circuit 200 can input another external power source EVIN and output a voltage VOUT corresponding to the external power source EVIN. For example, the first voltage generating circuit 200 can convert the external power source EVIN to output a corresponding voltage VOUT. Alternatively, the first voltage generating circuit 200 can control the on / off state of the external power source EVIN circuit so that when the circuit is on, the output voltage VOUT equals the voltage of the external power source EVIN.

[0042] When the power supply with a wide output voltage range is in operation, it requires a control power supply VDD and a power supply VIN. For example, after the chip is powered on, it can provide the power supply with a wide output voltage range with a chip power supply and a low-power voltage source, which serve as the power supply VIN and control power supply VDD required by the power supply with a wide output voltage range, respectively. Furthermore, when the first voltage generating circuit 200 needs to output a voltage VOUT, it also needs to provide an external power supply EVIN to the first voltage generating circuit 200.

[0043] The working principle of the power supply with a wide output voltage range is as follows.

[0044] The external power detection circuit 100 can detect the input external power supply EVIN. If the external power supply EVIN meets the power supply requirements, the first voltage generation circuit 200 can output a voltage VOUT to provide external power. Specifically, the external power detection circuit 100 can output a first control signal. Upon receiving the first control signal, the first voltage generation circuit 200 can output a voltage VOUT corresponding to the external power supply EVIN. Furthermore, the second voltage generation circuit 300 does not respond to the first control signal. For example, upon receiving the first control signal, the second voltage generation circuit 300 can be in a shutdown state, meaning that the second voltage generation circuit 300 is inoperative. When powered by the first voltage generation circuit 200, the power consumed is the power of the external power supply EVIN, and essentially no internal power consumption of the chip, i.e., the power supply VIN, is consumed. This allows the power supply with a wide output voltage range to operate in a low-power state.

[0045] Furthermore, the external power supply EVIN may not meet the power supply requirements; for example, the external power supply EVIN is not currently being input; the external power supply EVIN voltage is too low; or a lower voltage output is currently required, but the external power supply EVIN voltage is too high. If the external power supply EVIN does not meet the power supply requirements, the second voltage generation circuit 300 is required to output the voltage VOUT. In this case, the first voltage generation circuit 200 is inoperative, meaning that the control signal output by the external power detection circuit 100 selects either the first voltage generation circuit 200 or the second voltage generation circuit 300 to be operational.

[0046] Specifically, the external power detection circuit 100 can output a second control signal that can be responded to by the second voltage generation circuit 300. After receiving the second control signal, the second voltage generation circuit 300 can convert the connected power supply VIN to output a corresponding voltage VOUT. In addition, the first voltage generation circuit 200 does not respond to the second control signal; for example, after receiving the second control signal, the first voltage generation circuit 200 can be in a shutdown state, that is, the first voltage generation circuit 200 does not operate.

[0047] Among them, the power supply can control the working conditions of the first voltage generating circuit 200 and the second voltage generating circuit 300 as needed, so that different voltages VOUT can be output to the outside; and the external power supply EVIN itself is variable, and its voltage can vary within a certain range. Therefore, when the first voltage generating circuit 200 supplies power to the outside, it can also output the corresponding voltage VOUT to the outside by connecting to an external power supply EVIN of different voltages, ensuring that the power supply can have a wider output voltage range.

[0048] The power supply with a wide output voltage range provided in this embodiment can control different voltage generation circuits to provide external power. Furthermore, the external power supply EVIN that meets the power supply requirements can operate within a wide voltage range, enabling the power supply to have a wide output voltage range. Furthermore, the first voltage generation circuit 200 is powered by the external power supply EVIN. When the first voltage generation circuit 200 is operating, it consumes the power of the external power supply EVIN. This significantly reduces the power consumption of the power supply with a wide output voltage range, placing it in a low-power state and ensuring low overall power consumption.

[0049] In some optional embodiments, as shown in Figure 2, the external power detection circuit 100 includes: a current source B1, a first switch tube M1, a second switch tube M2, a third switch tube M3, a fourth switch tube M4, a fifth switch tube M5, a sixth switch tube M6, a seventh switch tube M7, an eighth switch tube M8, a ninth switch tube M9, a tenth switch tube M10, a first resistor R1, a second resistor R2 and a first inverter A1; wherein the first switch tube M1, the second switch tube M2, the seventh switch tube M7, the eighth switch tube M8, the ninth switch tube M9 and the tenth switch tube M10 are NPN-type transistors or N-type field-effect transistors; and the third switch tube M3, the fourth switch tube M4, the fifth switch tube M5 and the sixth switch tube M6 are PNP-type transistors or P-type field-effect transistors.

[0050] In this embodiment, the switch tube has a control terminal, a current input terminal, and a current output terminal. Under the control of the control terminal, the switch tube can control whether the current input terminal and the current output terminal are conductive. For example, if the switch tube is an NPN-type transistor, its base is the control terminal, the collector is the current input terminal, and the emitter is the current output terminal. If the switch tube is an N-type field-effect transistor, such as an NMOS transistor, its gate is the control terminal, the drain is the current input terminal, and the source is the current output terminal. If the switch tube is a PNP-type transistor, its base is the control terminal, the emitter is the current input terminal, and the collector is the current output terminal. If the switch tube is a P-type field-effect transistor, such as a PMOS transistor, its gate is the control terminal, the source is the current input terminal, and the drain is the current output terminal. Among them, taking the first switch tube M1 and the second switch tube M2 as an example, the first switch tube M1 and the second switch tube M2 can both be NPN-type transistors, or both are N-type field-effect transistors. This embodiment does not limit this. Figure 2 shows an example in which both are N-type field-effect transistors; similarly, the remaining switch tubes in Figure 2 are also field-effect transistors.

[0051] As shown in FIG2 , the input end of the current source B1 is configured to be connected to the control power supply VDD, and the output end of the current source B1 is connected to the current input end of the first switch tube M1 .

[0052] The control end of the first switch tube M1 and the control end of the second switch tube M2 are both connected to the current input end of the first switch tube M1 ; the current output end of the first switch tube M1 and the current output end of the second switch tube M2 are grounded.

[0053] One end of the first resistor R1 is connected to the external power supply EVIN, and the other end is connected to ground via the second resistor R2. As shown in FIG2, the first resistor R1 and the second resistor R2 form a series structure, which is connected in series between the external power supply EVIN and ground (GND).

[0054] As shown in FIG2 , the current input terminals of the third switch tube M3 , the fourth switch tube M4 , the fifth switch tube M5 , and the sixth switch tube M6 are all configured to be connected to the control power supply VDD.

[0055] The control end of the third switch tube M3 and the control end of the fourth switch tube M4 are both connected to the current output end of the fourth switch tube M4; the current output end of the third switch tube M3 is connected to the current input end of the ninth switch tube M9, and the current output end of the fourth switch tube M4 is connected to the current input end of the seventh switch tube M7.

[0056] The control terminal of the fifth switch M5 and the control terminal of the sixth switch M6 are both connected to the current output terminal of the fifth switch M5; the current output terminal of the fifth switch M5 is connected to the current input terminal of the eighth switch M8, and the current output terminal of the sixth switch M6 is connected to the current input terminal of the tenth switch M10, and is also connected to the input terminal of the first inverter A1. Furthermore, the output terminal of the first inverter A1 serves as the output terminal of the external power detection circuit 100. As shown in Figure 2, point A represents the current output terminal of the sixth switch M6, which is also the input terminal of the first inverter A1, and point B represents the output terminal of the first inverter A1, which is also the output terminal of the external power detection circuit 100. It can be understood that point B can provide corresponding first and second control signals to the first voltage generation circuit 200 and the second voltage generation circuit 300.

[0057] The control terminal of the seventh switch M7 is configured to receive the first reference voltage VREF1. The control terminal of the eighth switch M8 is connected to the end of the first resistor R1 that is closest to the second resistor R2. The current output terminals of the seventh and eighth switches M7 and M8 are both connected to the current input terminal of the second switch M2. The control terminals of the ninth and tenth switches M9 and M10 are both connected to the current input terminal of the ninth switch M9. The current output terminals of the ninth and tenth switches M9 and M10 are grounded. The seventh and eighth switches M7 and M8 have the same parameters, such as the same width-to-length ratio.

[0058] In this embodiment, the connection node between the first resistor R1 and the second resistor R2 is referred to as point C. It can be understood that the voltage VC at point C is: Wherein, R1 is the resistance value of the first resistor, and R2 is the resistance value of the second resistor.

[0059] Generally, external power supply EVIN is considered to meet power supply requirements only when it is sufficiently high. Therefore, if the first reference voltage VREF1 is less than the voltage VC at point C, external power supply EVIN is considered to meet power supply requirements. For example, in this case, the voltage VA at point A is high. After the action of first inverter A1, the voltage at point B at its output terminal is low. External power supply detection circuit 100 can output a low-level control signal, which is the first control signal.

[0060] If the first reference voltage VREF1 is greater than the voltage VC at point C, it can be determined that the external power supply EVIN does not meet the power supply requirements. For example, if the external power supply EVIN is not currently connected, the voltage VC at point C is 0, which is less than the first reference voltage VREF1. In this case, the first voltage generation circuit 200 can output a corresponding voltage. For example, if the voltage VA at point A is low, the voltage at point B at its output terminal is high due to the action of the first inverter A1. The external power supply detection circuit 100 can then output a high-level control signal, which is the second control signal.

[0061] In this embodiment, the working principle of the external power detection circuit 100 shown in FIG2 is specifically as follows.

[0062] When the power supply is operating, it is connected to the control power supply VDD. For example, after the chip is connected to the chip power supply, a low-power, low-voltage source is generated within the chip. This chip power supply serves as the power supply VIN, and this low-power, low-voltage source serves as the control power supply VDD, which can power the external power detection circuit 100. At this time, current source B1 generates a current, which, for ease of description, is referred to as the first current I1. This first current I1 pulls up the control terminals of the first and second switching transistors M1 and M2, turning them on. Furthermore, the first reference voltage VREF1 can be a reference voltage generated by the chip's internal power supply. For example, after the chip power supply VIN is connected to a power supply with a wide output voltage range, the first reference voltage VREF1 can be input to the control terminal of the seventh switching transistor M7.

[0063] Specifically, the first reference voltage VREF1 is input to the control terminal of the seventh switch M7, turning on the seventh switch M7. At this point, the control terminal voltages of the third and fourth switches M3 and M4 are pulled down by the turned-on seventh switch M7 and second switch M2, turning on the third and fourth switches M3 and M4. Consequently, current flows through the branch formed by the fourth, seventh, and second switches M4. Furthermore, the turned-on third switch M3 pulls up the control terminal voltages of the ninth and tenth switches M9 and M10, turning on the ninth and tenth switches M9 and M10. Consequently, current also flows through the branch formed by the third and ninth switches M3 and M9. Furthermore, because the ninth and tenth switches M9 and M10 form a current mirror structure, a pull-down current is generated at point A in the tenth switch M10, thereby lowering the voltage at point A.

[0064] When the external power supply EVIN is not connected to the power supply with a wide output voltage range, the voltage at point C is low, the eighth switch tube M8 is turned off, causing the fifth switch tube M5 and the sixth switch tube M6 to also turn off, which does not affect the voltage at point A. Therefore, the voltage at point A is low at this time, and the voltage at point B at the output end of the first inverter A1 is high. Therefore, the external power detection circuit 100 can output a high-level second control signal at this time.

[0065] When the external power supply EVIN is connected to the power supply with a wide output voltage range, the voltage VC at point C is the divided voltage obtained by the first resistor R1 and the second resistor R2. Therefore, at this time, the voltage VC at point C can pull up the voltage at the control terminal of the eighth switch M8, turning on the eighth switch M8. Subsequently, the voltages at the control terminals of the fifth and sixth switches M5 and M6 are pulled down by the turned-on eighth and second switches M8 and M2, turning on the fifth and sixth switches M5 and M6. Therefore, current flows through the branch formed by the fifth, eighth, and second switches M5, M8, and M2. At the same time, because the fifth and sixth switches M5 and M6 form a current mirror structure, a charging current at point A is generated in the sixth switch M6, which can pull up the voltage at point A.

[0066] At this time, the current flowing through the seventh switch M7 is referred to as the second current I2, and the current flowing through the eighth switch M8 is referred to as the third current I3. Referring to the structure shown in FIG2 , it can be seen that the second current I2 flowing through the seventh switch M7 and the current flowing through the third switch M3 have a linear relationship, which is specifically related to the width-to-length ratio of the third switch M3 to the fourth switch M4. If the third switch M3 and the fourth switch M4 have the same width-to-length ratio, then the second current I2 flowing through the seventh switch M7 equals the current flowing through the third switch M3.

[0067] The current flowing through the third switching transistor M3 = the current flowing through the ninth switching transistor M9. Similarly, the current flowing through the ninth switching transistor M9 has a linear relationship with the current flowing through the tenth switching transistor M10, and the current flowing through the tenth switching transistor M10 is the pull-down current at point A.

[0068] Moreover, the third current flowing through the eighth switching transistor M8 = the current flowing through the fifth switching transistor M5. The current flowing through the fifth switching transistor M5 has a linear relationship with the current flowing through the sixth switching transistor M6, and the current flowing through the sixth switching transistor M6 is the charging current at point A.

[0069] Since the current output terminals of the seventh switching transistor M7 and the eighth switching transistor M8 are connected, at this time, the voltage difference between the control terminal and the current output terminal of the seventh switching transistor M7, and the voltage difference between the control terminal and the current output terminal of the eighth switching transistor M8 only depend on the magnitudes of the first reference voltage VREF1 and the voltage VC at point C. And, as described above, the charging current at point A and the pull-down current at point A also depend on the aspect ratios of the third switching transistor M3 and the fourth switching transistor M4, the aspect ratios of the fifth switching transistor M5 and the sixth switching transistor M6, and the aspect ratios of the ninth switching transistor M9 and the tenth switching transistor M10.

[0070] Among them, if the external power supply EVIN is too small, resulting in the third current I3 being small enough compared to the second current I2, at this time, the charging current at point A will be less than the pull-down current at point A, so point A remains at a low level; conversely, if the external power supply EVIN is too large, resulting in the third current I3 being large enough compared to the second current I2, at this time, the charging current at point A will be greater than the pull-down current at point A, and the voltage at point A can be pulled up, so the voltage at point A is at a high level.

[0071] For ease of description, assume that the aspect ratios of the third switching transistor M3 and the fourth switching transistor M4 are the same, the aspect ratios of the fifth switching transistor M5 and the sixth switching transistor M6 are the same, and the aspect ratios of the ninth switching transistor M9 and the tenth switching transistor M10 are the same. Subsequently, the operating principle of the circuit structure will be described under the condition that the aspect ratios are the same.

[0072] In this case, the second current I2 flowing through the seventh switching transistor M7 = the current flowing through the third switching transistor M3 = the current flowing through the ninth switching transistor M9 = the current flowing through the tenth switching transistor M10 = the pull-down current at point A, and the third current I3 flowing through the eighth switching transistor M8 = the current flowing through the fifth switching transistor M5 = the current flowing through the sixth switching transistor M6 = the charging current at point A.

[0073] When the voltage VC at point C is less than the first reference voltage VREF1, i.e., VC < VREF1; since the voltage at point C That is, when At this time, since the current output terminals of the seventh switch tube M7 and the eighth switch tube M8 are connected, the voltage difference between the control terminal and the current output terminal of the seventh switch tube M7 is greater than the voltage difference between the control terminal and the current output terminal of the eighth switch tube M8. Therefore, the second current I2 flowing through the seventh switch tube M7 is greater than the third current I3 flowing through the eighth switch tube M8. That is, at this time, the pull-down current at point A is greater than the charging current at point A, point A is still at a low level, and the circuit state remains the same as before the external power supply EVIN is connected. That is, the external power detection circuit 100 still outputs the second control signal of a high level.

[0074] When the voltage VC at point C is greater than the first reference voltage VREF1, that is, when When the voltage difference between the control terminal and the current output terminal of the seventh switch tube M7 is smaller than the voltage difference between the control terminal and the current output terminal of the eighth switch tube M8, the second current I2 flowing through the seventh switch tube M7 is smaller than the third current I3 flowing through the eighth switch tube M8. That is, at this time, the pull-down current at point A is smaller than the charging current at point A, point A is converted to a high level, and the voltage at the output terminal point B of the first inverter A1 is converted to a low level. That is, the external power detection circuit 100 outputs a low-level first control signal.

[0075] In this embodiment, the external power supply detection circuit 100 utilizes the first switch tube M1 and the second switch tube M2 to effectively control whether the external power supply detection circuit 100 as a whole is working; by utilizing multiple switch tubes, a suitable voltage can be output to the first inverter A1 based on the voltage of the external power supply EVIN, which not only ensures low power consumption, but also converts the voltage into a stable voltage through the first inverter A1, and can provide a unified low-level control signal or a high-level control signal for the subsequent first voltage generation circuit 200 and the second voltage generation circuit 300.

[0076] Optionally, if the external power supply EVIN is When the voltage fluctuates near the output voltage, it will cause the voltage at point A to fluctuate, causing the voltage at point B to switch repeatedly between high and low levels; in order to further improve the safety and reliability of the power supply with a wide output voltage range, a first hysteresis circuit and a second hysteresis circuit are added to the power supply.

[0077] As shown in FIG3 , the external power detection circuit 100 further includes: a first hysteresis circuit 101 and a second hysteresis circuit 102 ; the first hysteresis circuit 101 includes: a third resistor R3 and an eleventh switch tube M11 ; the eleventh switch tube M11 is an NPN transistor or an N-type field effect transistor.

[0078] In this embodiment, the second resistor R2 is not directly grounded, but is grounded through a third resistor R3. As shown in Figure 3, one end of the third resistor R3 is connected to the end of the second resistor R2 away from the first resistor R1, and the other end of the third resistor R3 is grounded; that is, the first resistor R1, the second resistor R2, and the third resistor R3 are connected in series in this order.

[0079] The control end of the eleventh switch tube M11 is connected to the output end of the first inverter A1; the current input end of the eleventh switch tube M11 is connected to the end of the third resistor R3 close to the second resistor R2; and the current output end of the eleventh switch tube M11 is grounded.

[0080] The second hysteresis circuit 102 is configured to provide a charging current to the current input terminal of the tenth switch tube M10 when the output terminal of the first inverter A1 is at a low level; when the output terminal of the first inverter A1 is at a high level, the second hysteresis circuit 102 does not work, which is equivalent to the absence of the second hysteresis circuit 102; for example, when the external power supply EVIN is sufficiently small, the output terminal of the first inverter A1 can be made high, and at this time the second hysteresis circuit 102 does not work.

[0081] In this embodiment, if the voltage VC at point C is less than the first reference voltage VREF1, point A is at a low level, and the output terminal of the first inverter A1 is at a high level, that is, point B is at a high level; at this time, the second hysteresis circuit 102 does not operate, and the control terminal of the eleventh switch tube M11 is at a high level, the eleventh switch tube M11 is turned on, and the third resistor R3 is short-circuited. Therefore, the operating principle of the external power detection circuit 100 at this time is the same as the circuit structure shown in FIG. 2 and will not be further described here.

[0082] If the voltage VC at point C is greater than the first reference voltage VREF1, point A is at a high level, and the output of the first inverter A1 is at a low level, then the second hysteresis circuit 102 can provide a charging current to the current input terminal of the tenth switch tube M10, that is, the second hysteresis circuit 102 can generate a charging current at point A, further ensuring that the charging current at point A is greater than the pull-down current at point A, thereby ensuring that point A is in a high level state. In addition, the control terminal of the eleventh switch tube M11 is at a low level, and the eleventh switch tube M11 is turned off, so that the third resistor R3 is connected to the circuit. Therefore, the voltage at point C is In this case, only when the external power supply EVIN is less than In other words, when the external power supply EVIN is greater than When , point A can still be guaranteed to be at a high level, that is, the output end of the first inverter A1 can still be guaranteed to be at a low level.

[0083] Therefore, when the external power supply EVIN is When the fluctuation is near Greater than Therefore, the external power supply EVIN is still greater than It can be ensured that when the external power supply EVIN fluctuates, the output end of the first inverter A1 remains at a low level.

[0084] Optionally, as shown in FIG3 , the second hysteresis circuit 102 includes: a twelfth switch tube M12 and a thirteenth switch tube M13 ; the twelfth switch tube M12 and the thirteenth switch tube M13 are PNP transistors or P-type field effect transistors.

[0085] The control terminal of the twelfth switch M12 is connected to the control terminal of the fifth switch M5. The current input terminal of the twelfth switch M12 is configured to be connected to the control power supply VDD. The current output terminal of the twelfth switch M12 is connected to the current input terminal of the thirteenth switch M13. The control terminal of the thirteenth switch M13 is connected to the output terminal of the first inverter A1, and the current output terminal of the thirteenth switch M13 is connected to the current input terminal of the tenth switch M10.

[0086] In this embodiment, if the voltage VC at point C is lower than the first reference voltage VREF1, the output terminal of the first inverter A1 is at a high level, that is, point B is at a high level. Therefore, the control terminals of the eleventh switch tube M11 and the thirteenth switch tube M13 are both at a high level, the eleventh switch tube M11 is turned on, and the thirteenth switch tube M13 is turned off. Regardless of the state of the twelfth switch tube M12, the second hysteresis circuit 102 is turned off and does not provide additional charging current to point A.

[0087] If the external power supply EVIN is connected to the power supply with wide output voltage range, and the voltage at point C is Greater than the first reference voltage VREF1, that is, the external power supply EVIN is greater than When the charging current flowing from the sixth switch tube M6 into point A is greater than the pull-down current flowing from point A into the tenth switch tube M10, point A is converted to a high level, the voltage at the output terminal point B of the first inverter A1 is converted to a low level, the thirteenth switch tube M13 is turned on, and the eleventh switch tube M11 is turned off; and the turned-on eighth switch tube M8 can pull down the control terminal of the twelfth switch tube M12, so that the twelfth switch tube M12 is turned on.

[0088] At this time, the branch formed by the twelfth switch tube M12 and the thirteenth switch tube M13 can also generate a charging current flowing into point A, thereby further ensuring that the charging current at point A is greater than the pull-down current at point A, ensuring that point A is in a high level state; at the same time, the third resistor R3 is connected to the circuit so that only when the external power supply EVIN is less than When the voltage VC at point C is less than the first reference voltage VREF1, the external power detection circuit 100 may be converted to output high level, thereby ensuring that when the external power EVIN is When the voltage fluctuates near the input voltage, the control signal output by the external power supply detection circuit 100 will not be repeatedly switched, and the first voltage generating circuit 200 and the second voltage generating circuit 300 will not be repeatedly switched, thereby improving the safety and reliability of the power supply with a wide output voltage range.

[0089] In this embodiment, if the second hysteresis circuit 102 includes only the thirteenth switch M13 but not the twelfth switch M12, then after the output of the first inverter A1 is at a low level, the voltage at point A will be directly pulled up to the control power supply VDD by the thirteenth switch M13. Thereafter, even if the eighth switch M8 is turned off and the fifth switch M5 and the sixth switch M6 are also turned off, point A may still be pulled up to the control power supply VDD. The current flowing through the tenth switch M10 (i.e., the pull-down current at point A) cannot pull the voltage at point A down, which may easily cause the external power detection circuit 100 to always output a low level, forming an infinite loop.

[0090] If the second hysteresis circuit 102 includes only the twelfth switch M12 and not the thirteenth switch M13, first, to ensure current balance during normal circuit operation, when the voltage at point C is equal to the first reference voltage VREF1, the charging current flowing from the sixth switch M6 into point A (in this case, only the sixth switch M6 is flowing, i.e., the second hysteresis circuit 102 is not considered) is designed to be equal to the pull-down current flowing from point A into the tenth switch M10. If the second hysteresis circuit 102 includes only the twelfth switch M12, the twelfth switch M12 will be turned on as long as the voltage at point C is greater than the threshold voltage of the eighth switch M8. In this case, even if the voltage at point C is less than the first reference voltage VREF1, the charging current flowing into point A (the current flowing through the sixth switch M6 + the current flowing through the twelfth switch M12) is significantly greater than the pull-down current flowing from point A into the tenth switch M10, making current balance impossible. If the current flowing through the sixth switch tube M6 + the current flowing through the twelfth switch tube M12 is designed in advance to be equal to the pull-down current flowing from point A into the tenth switch tube M10, then the purpose of further increasing the charging current after the voltage at point A becomes higher cannot be achieved.

[0091] In some optional embodiments, as shown in FIG4 , the first voltage generating circuit 200 includes a response circuit 201 and a switch circuit 202. The response circuit 201 responds to the control signal output by the external power detection circuit 100 and outputs a corresponding control signal to the switch circuit 202. Furthermore, the switch circuit 202 does not convert the external power source EVIN, but serves as a switch that controls whether to use the external power source EVIN for power supply.

[0092] Specifically, as shown in FIG4 , the input of the response circuit 201 is connected to the output of the external power detection circuit 100. For example, the input of the response circuit 201 is connected to point B of the external power detection circuit 100 shown in FIG2 , etc.; the output of the response circuit 201 is connected to the control terminal of the switch circuit 202. The response circuit 201 is configured to convert the first control signal into a third control signal and the second control signal into a fourth control signal. The third and fourth control signals can have different high and low levels, for example, the third control signal can be a high level and the fourth control signal can be a low level.

[0093] The input end of the switch circuit 202 is configured to be connected to the external power supply EVIN, and the output end of the switch circuit 202 serves as the output end of the first voltage generating circuit 200; the switch circuit 202 is configured so that when a third control signal is input to the control end of the switch circuit 202, the input end and the output end of the switch circuit 202 are turned on; when a fourth control signal is input to the control end of the switch circuit 202, the input end and the output end of the switch circuit 202 are turned off.

[0094] In this embodiment, when the external power supply EVIN meets the power supply requirements, the external power supply detection circuit 100 outputs a first control signal, and the response circuit 201 converts the first control signal into a third control signal and inputs it to the switch circuit 202; under the action of the third control signal, the input and output ends of the switch circuit 202 are turned on, so that the output end of the first voltage generating circuit 200 can be connected to the external power supply EVIN, thereby directly using the external power supply EVIN for external power supply. At this time, the voltage VOUT provided is also the voltage of the external power supply EVIN.

[0095] When the external power supply EVIN does not meet the power supply requirements, the external power supply detection circuit 100 outputs a second control signal, and the response circuit 201 converts the second control signal into a fourth control signal and inputs it to the switch circuit 202; under the action of the fourth control signal, the input and output ends of the switch circuit 202 are turned off, that is, the output end of the first voltage generating circuit 200 is in a turned-off state, and it is not connected to the external power supply EVIN. At this time, the first voltage generating circuit 200 does not supply power to the outside, and the second voltage generating circuit 300 can output the required voltage VOUT to the outside.

[0096] Optionally, the first control signal is at a low level and the second control signal is at a high level. Furthermore, as shown in FIG4 , the response circuit 201 may specifically include: a second inverter A2, a third inverter A3, a fourteenth switch transistor M14, a fifteenth switch transistor M15, a sixteenth switch transistor M16, and a seventeenth switch transistor M17; the fourteenth switch transistor M14 and the fifteenth switch transistor M15 are PNP transistors or P-type field-effect transistors, and the sixteenth switch transistor M16 and the seventeenth switch transistor M17 are NPN transistors or N-type field-effect transistors. And / or, the switch circuit 202 may specifically include: a fourth inverter A4 and an eighteenth switch transistor M18; the eighteenth switch transistor M18 is a P-type field-effect transistor.

[0097] As shown in FIG4 , the input end of the second inverter A2 is connected to the output end of the external power detection circuit 100 , and the output end of the second inverter A2 is connected to the input end of the third inverter A3 .

[0098] The current input terminals of the fourteenth switch tube M14 and the fifteenth switch tube M15 are connected to the output terminal of the first voltage generating circuit 200, which can be connected to the output voltage VOUT; the control terminal of the fourteenth switch tube M14 is connected to the current output terminal of the fifteenth switch tube M15, and the control terminal of the fifteenth switch tube M15 is connected to the current output terminal of the fourteenth switch tube M14.

[0099] The control terminal of the sixteenth switch M16 is connected to the output terminal of the third inverter A3. The current input terminal of the sixteenth switch M16 is connected to the current output terminal of the fourteenth switch M14. The current output terminal of the sixteenth switch M16 is grounded. The current output terminal of the fourteenth switch M14 is also connected to the control terminal of the switch circuit 202. The current output terminal of the fourteenth switch M14 can serve as the output terminal of the response circuit 201.

[0100] The control end of the seventeenth switch tube M17 is connected to the output end of the second inverter A2 , the current input end of the seventeenth switch tube M17 is connected to the current output end of the fifteenth switch tube M15 , and the current output end of the seventeenth switch tube M17 is grounded.

[0101] 4 , the input of the fourth inverter A4 is connected to the output of the response circuit 201, and the output of the fourth inverter A4 is connected to the control terminal of the eighteenth switch tube M18; the drain of the eighteenth switch tube M18 is configured to be connected to the external power supply EVIN, and the source of the eighteenth switch tube M18 serves as the output of the first voltage generating circuit 200.

[0102] In this embodiment, as shown in FIG4 , the power source connected to the current input terminals of the fourteenth switch tube M14 and the fifteenth switch tube M15 may be the voltage VOUT output by the power source.

[0103] As shown in FIG4 , if the external power detection circuit 100 outputs a high-level second control signal, i.e., point B is high, the voltage at the output terminal of the second inverter A2 is low. Therefore, the third inverter A3 outputs a high-level signal to the control terminal of the sixteenth switch M16. Furthermore, the voltage at the control terminal of the seventeenth switch M17 is low. Therefore, the sixteenth switch M16 is turned on, while the seventeenth switch M17 is turned off. Consequently, the voltage at the control terminal of the fifteenth switch M15 is pulled down by the turned-on sixteenth switch M16, turning on the fifteenth switch M15. At this point, the control terminal of the fourteenth switch M14 is pulled up to the output voltage VOUT by the fifteenth switch M15. Furthermore, since the voltage at the current input terminal of the fourteenth switch M14 is also the output voltage VOUT, the fourteenth switch M14 is turned off. Consequently, the voltage at the output terminal of the response circuit 201 is pulled down by the sixteenth switch M16, reaching a low level. Furthermore, the input terminal of the fourth inverter A4 is at a low level, so the fourth inverter A4 outputs a high level, the eighteenth switch M18 is in the off state, and the external power supply EVIN is not supplying power. At this time, the second voltage generating circuit 300 can output the voltage VOUT.

[0104] If the external power detection circuit 100 outputs a low-level first control signal, that is, point B is at a low level, the voltage at the output terminal of the second inverter A2 is converted to a high level. At this time, the third inverter A3 outputs a low level to the control terminal of the sixteenth switch tube M16, and the voltage at the control terminal of the seventeenth switch tube M17 is at a high level. Therefore, the sixteenth switch tube M16 is turned off and the seventeenth switch tube M17 is turned on. Therefore, the voltage at the control terminal of the fourteenth switch tube M14 is pulled down by the turned-on seventeenth switch tube M17, and the fourteenth switch tube M14 is turned on. At this time, The control terminal of the fifteenth switch M15 is pulled to the output voltage VOUT by the fourteenth switch M14. Since the voltage at the current input terminal of the fifteenth switch M15 is also the output voltage VOUT, the fifteenth switch M15 is turned off. At this point, the voltage at the input terminal of the fourth inverter A4 is pulled up to the output voltage VOUT by the fourteenth switch M14. Therefore, the fourth inverter A4 outputs a low level, turning on the eighteenth switch M18. The external power supply EVIN can output the voltage VOUT through the eighteenth switch M18. At this point, the output voltage VOUT of the power supply with a wide output voltage range is clamped to the external power supply EVIN.

[0105] When the external power supply EVIN meets the power supply requirements, the second voltage generating circuit 300 does not work; and when the external power supply EVIN is large enough, the source voltage of the eighteenth switch tube M18 can be pulled up to EVIN-VD18 through the body diode of the eighteenth switch tube M18; wherein the source voltage of the eighteenth switch tube M18 is the output voltage VOUT of the first voltage generating circuit 200, and VD18 is the voltage drop of the body diode of the eighteenth switch tube M18.

[0106] Furthermore, when the external power supply EVIN is low, the first voltage generating circuit 200 does not operate, and the second voltage generating circuit 300 outputs the voltage VOUT. To ensure that the external power supply EVIN does not affect the output voltage VOUT, when the second voltage generating circuit 300 is operating, the maximum allowable value of the external power supply EVIN must be less than the sum of the voltage VOUT output by the second voltage generating circuit 300 and the body diode voltage drop VD18 of the eighteenth switch M18. In other words, the maximum value of EVIN is less than the output voltage VOUT + VD18 at this time.

[0107] For example, for the external power detection circuit 100 shown in FIG2 , in order to ensure that the second voltage generating circuit 300 can work, the external power EVIN is less than That is, the maximum value of EVIN is In addition, the second voltage generating circuit 300 can output a fixed voltage VOUT. For example, the output voltage VOUT of the second voltage generating circuit 300 shown in FIG. 5 is: (For details, please refer to the subsequent related description.) Therefore, in order to ensure that the body diode of the eighteenth switch tube M18 is not conducting when the second voltage generating circuit 300 is operating, the two voltage generating circuits need to meet the following requirements:

[0108] In this embodiment, the switch circuit 202 serves as a switch for determining whether to use the external power supply EVIN for power supply. It does not require a complex circuit structure, can simplify the circuit structure, and ensure low power consumption. In addition, the fourteenth switch tube M14, the fifteenth switch tube M15, the sixteenth switch tube M16, and the seventeenth switch tube M17 can respond to the control signal (including the first control signal and the second control signal), thereby outputting a suitable control signal to the switch circuit.

[0109] In some optional embodiments, as shown in Figure 5, the second voltage generating circuit 300 includes: a power supply switch tube M0, the current input end of the power supply switch tube M0 is configured to be connected to the power supply VIN, and the current output end of the power supply switch tube M0 serves as the output end of the second voltage generating circuit 300, which can output a corresponding voltage VOUT.

[0110] 5 , the second voltage generating circuit 300 further includes: a fourth resistor R4, a fifth resistor R5, a nineteenth switch tube M19, a twentieth switch tube M20, a twenty-first switch tube M21, a twenty-second switch tube M22, a twenty-third switch tube M23, a twenty-fourth switch tube M24, a twenty-fifth switch tube M25, a twenty-sixth switch tube M26, a twenty-seventh switch tube M27, and a twenty-eighth switch tube M28; wherein the nineteenth switch tube M19, the twentieth switch tube M20, the twenty-first switch tube M21, and the twenty-second switch tube M22 are PNP-type transistors or P-type field-effect transistors; and the twenty-third switch tube M23, the twenty-fourth switch tube M24, the twenty-fifth switch tube M25, the twenty-sixth switch tube M26, the twenty-seventh switch tube M27, and the twenty-eighth switch tube M28 are NPN-type transistors or N-type field-effect transistors.

[0111] As shown in FIG5 , one end of the fourth resistor R4 is connected to the current output end of the power switch tube M0 , and the other end is grounded via the fifth resistor R5 .

[0112] Current input terminals of the nineteenth switch tube M19 , the twentieth switch tube M20 , the twenty-first switch tube M21 , and the twenty-second switch tube M22 are all configured to be connected to the power supply VIN.

[0113] The control end of the nineteenth switch tube M19 and the control end of the twentieth switch tube M20 are both connected to the current output end of the twentieth switch tube M20; the current output end of the nineteenth switch tube M19 is connected to the current input end of the twenty-third switch tube M23, and the current output end of the twentieth switch tube M20 is connected to the current input end of the twenty-fifth switch tube M25.

[0114] The control end of the twenty-first switch tube M21 and the control end of the twenty-second switch tube M22 are both connected to the current output end of the twenty-first switch tube M21; the current output end of the twenty-first switch tube M21 is connected to the current input end of the twenty-sixth switch tube M26, and the current output end of the twenty-second switch tube M22 is connected to the current input end of the twenty-fourth switch tube M24, and is also connected to the control end of the power supply switch tube M0. Point E in FIG5 represents the control end of the power supply switch tube M0, which controls the on and off of the power supply switch tube M0.

[0115] The control end of the twenty-third switch tube M23 and the control end of the twenty-fourth switch tube M24 are both connected to the current input end of the twenty-third switch tube M23; the current output end of the twenty-third switch tube M23 and the current output end of the twenty-fourth switch tube M24 are both connected to the current input end of the twenty-seventh switch tube M27.

[0116] The control terminal of the twenty-fifth switch M25 is configured to be connected to the second reference voltage VREF2, and the control terminal of the twenty-sixth switch M26 is connected to the end of the fourth resistor R4 close to the fifth resistor R5, that is, connected to point D in Figure 5; the current output terminal of the twenty-fifth switch M25 and the current output terminal of the twenty-sixth switch M26 are both connected to the current input terminal of the twenty-eighth switch M28. It can be understood that the voltage at point D is R4 is the resistance of the fourth resistor R4, and R5 is the resistance of the fifth resistor R5. The twenty-fifth switch M25 and the twenty-sixth switch M26 have the same parameters, for example, the same width-to-length ratio.

[0117] The control terminals of the twenty-seventh switch M27 and the twenty-eighth switch M28 are both connected to the output terminal of the external power detection circuit 100; for example, they can be connected to point B of the external power detection circuit 100 shown in FIG2 . The current output terminals of the twenty-seventh switch M27 and the twenty-eighth switch M28 are grounded.

[0118] In this embodiment, the first control signal is at a low level, and the second control signal is at a high level. In conjunction with the external power detection circuit 100 shown in FIG2 , the working principle of the second voltage generating circuit 300 shown in FIG5 is specifically as follows.

[0119] When the external power supply EVIN is not connected, or the external power supply EVIN is relatively low, the output terminal B of the external power supply detection circuit 100 is at a high level, and it outputs a high-level second control signal. Since point B is at a high level, the control terminal voltages of the twenty-seventh switch tube M27 and the twenty-eighth switch tube M28 are pulled up, and the twenty-seventh switch tube M27 and the twenty-eighth switch tube M28 are turned on. At the same time, after the power supply VIN is connected to the power supply with a wide output voltage range, the second reference voltage VREF2 can be input to the control terminal of the twenty-fifth switch tube M25, and the twenty-fifth switch tube M25 is turned on. At this time, the control terminal voltages of the nineteenth switch tube M19 and the twentieth switch tube M20 are pulled down through the twenty-fifth switch tube M25 and the twenty-eighth switch tube M28, and the nineteenth switch tube M19 and the twenty-fifth switch tube M25 are turned on. The 20th switch M20 is turned on, and the control terminal voltages of the 23rd and 24th switches M23 and M24 are pulled up via the 19th switch M19. The 23rd and 24th switches M23 and M24 are turned on. Consequently, current flows through the branch formed by the 20th, 25th, and 28th switches M20 and M25. Because the 19th and 20th switches M19 and M20 form a current mirror structure, current also flows through the branch formed by the 19th, 23rd, and 27th switches M19 and M27. Furthermore, because the 23rd and 24th switches M23 and M24 form a current mirror structure, a pull-down current is generated at point E in the 24th switch M24, lowering the voltage at point E. This causes point E to be at a low level, thereby turning on the power supply switch M0. At this time, current is generated in the branch formed by the power supply switch M0, the fourth resistor R4, and the fifth resistor R5, causing the voltage at point D to increase. This increases the voltage at the control terminal of the twenty-sixth switch M26, turning on the twenty-sixth switch M26. At this time, the voltage at the control terminals of the twenty-first and twenty-second switches M21, M22 are pulled down via the twenty-sixth and twenty-eighth switches M26, M28, turning on the twenty-first and twenty-second switches M21, M22. Therefore, current is also generated in the branch formed by the twenty-first, twenty-sixth, and twenty-eighth switches M21, M26, and M28. At this time, because the twenty-first and twenty-second switches M21, M22 form a current mirror structure, a charging current is generated in the twenty-second switch M22 at point E, which can increase the voltage at point E.

[0120] The current flowing through the twenty-fifth switch M25 is denoted as the fourth current I4, and the current flowing through the twenty-sixth switch M26 is denoted as the fifth current I5. Assuming that the nineteenth switch M19 and the twentieth switch M20 have the same width-to-length ratio, the twenty-first switch M21 and the twenty-second switch M22 have the same width-to-length ratio, and the twenty-third switch M23 and the twenty-fourth switch M24 have the same width-to-length ratio, combined with the structure of FIG5 , it can be seen that the fourth current I4 flowing through the twenty-fifth switch M25 = the current flowing through the nineteenth switch M19 = the current flowing through the twenty-third switch M23 = the current flowing through the twenty-fourth switch M24 = the pull-down current at point E, and the fifth current I5 flowing through the twenty-sixth switch M26 = the current flowing through the twenty-first switch M21 = the current flowing through the twenty-second switch M22 = the charging current at point E.

[0121] If the current flowing through the fifth resistor R5 is small and the voltage at point D is low and lower than the second reference voltage VREF2, since the current output terminals of the twenty-fifth switch M25 and the twenty-sixth switch M26 are connected, the voltage difference between the control terminal and the current output terminal of the twenty-fifth switch M25 is greater than the voltage difference between the control terminal and the current output terminal of the twenty-sixth switch M26. Therefore, the fourth current I4 flowing through the twenty-fifth switch M25 is greater than the fifth current I5 flowing through the twenty-sixth switch M26. That is, at this time, the pull-down current at point E is greater than the charging current at point E. Point E remains at a low level, the power supply switch M0 remains on, and the current flowing through the fifth resistor R5 continues to increase.

[0122] When the current flowing through the fifth resistor R5 increases to a certain value, causing the voltage at point D to be higher than the second reference voltage VREF2, the voltage difference between the control terminal and the current output terminal of the twenty-fifth switch tube M25 is smaller than the voltage difference between the control terminal and the current output terminal of the twenty-sixth switch tube M26. Therefore, the fourth current I4 flowing through the twenty-fifth switch tube M25 is smaller than the fifth current I5 flowing through the twenty-sixth switch tube M26. That is, at this time, the pull-down current at point E is smaller than the charging current at point E. Point E switches to a high level, the power supply switch tube M0 is turned off, the current flowing through the fifth resistor R5 decreases, and the voltage at point D drops again to below the second reference voltage VREF2. This cycle then repeats.

[0123] Therefore, when the second voltage generating circuit 300 is in a stable state, the voltage at point D is equal to the second reference voltage VREF2, that is, Therefore, at this time, the output voltage VOUT of the power supply with a wide output voltage range is a fixed voltage.

[0124] Conversely, if the external power supply EVIN meets the power supply requirements, for example, if the external power supply EVIN is sufficiently large, the output terminal B of the external power supply detection circuit 100 is at a low level, and the circuit outputs a low-level first control signal. Because point B is at a low level, the control terminal voltages of the twenty-seventh and twenty-eighth switching transistors M27 and M28 are both at a low level, turning off the twenty-seventh and twenty-eighth switching transistors M27 and M28, and the entire second voltage generation circuit 300 is inoperative.

[0125] In this embodiment, the primary power-consuming device of the second voltage generation circuit 300 is the power switch M0. The remaining devices (e.g., the nineteenth through twenty-eighth switches M19, M28, etc.) primarily serve a control function and thus have relatively low power consumption. Furthermore, the second voltage generation circuit 300 is adapted to output a voltage VOUT that is relatively close to the power supply VIN. In this case, due to the small voltage difference between the power supply VIN and the voltage VOUT, the operating current flowing through the power switch M0 is relatively low. Consequently, the second voltage generation circuit 300 consumes relatively low power, thereby ensuring low power consumption for the entire power supply.

[0126] In addition, whether to connect the external power supply EVIN or the size of the connected external power supply EVIN may be determined based on the size of the power supply VIN and the required size of the output voltage VOUT.

[0127] Specifically, if the voltage of the power supply VIN is small, the power supply VIN is The difference between them is small and the output voltage is fixed If the current application scenario of the chip can be met, the power supply with a wide output voltage range can be directly used to output a fixed voltage. At this time, since the power supply VIN is The difference between them is small, so that the operating current in the power supply switch tube M0 in the second voltage generating circuit 300 is small, and the power consumption of the second voltage generating circuit 300 is low, thereby ensuring that the power consumption of the entire power supply is also low.

[0128] If the voltage of the power supply VIN is large, the power supply VIN will be different from the fixed voltage. The difference between them is large, which results in a large power consumption of the second voltage generating circuit 300, or if the output fixed voltage The current application scenario of the chip cannot be satisfied. An external power supply EVIN can be connected to the power supply with a wide output voltage range. In order to prevent the first voltage generating circuit 200 from being triggered by mistake, when the external power supply EVIN is greater than When the second voltage generating circuit 300 is turned off, the first voltage generating circuit 200 can clamp the output voltage VOUT of the power supply with a wide output voltage range to the external power supply EVIN. At this time, since the output voltage VOUT is directly clamped to the external power supply EVIN, the power loss of the power supply with a wide output voltage range can also be greatly reduced.

[0129] At this time, the external power supply EVIN is greater than Furthermore, in order to prevent the body diode of the power switch tube M0 from conducting and affecting the circuit reliability, the external power supply EVIN must be less than VIN+VD0, where VD0 is the forward conduction voltage of the body diode of the power switch tube M0. Therefore, the external power supply EVIN can be greater than And it is smaller than any value of VIN+VD0, so a wider range of voltage output can be achieved.

[0130] Optionally, as shown in FIG6 , the second voltage generating circuit 300 further includes a zener diode Z1 and a sixth resistor R6. The zener diode Z1 and the sixth resistor R6 are connected in series and disposed between the current input terminal of the nineteenth switch M19 and the current output terminal of the twenty-third switch M23. The zener diode Z1 and the sixth resistor R6 can ensure that the voltage across the nineteenth switch M19 through the twenty-fourth switch M24 does not experience an overvoltage condition.

[0131] Optionally, as shown in FIG6 , the second voltage generating circuit 300 may further include: a twenty-ninth switch tube M29 and a thirtieth switch tube M30 ; the twenty-ninth switch tube M29 and the thirtieth switch tube M30 are NPN transistors or N-type field effect transistors.

[0132] The control end of the twenty-ninth switch tube M29 and the control end of the thirtieth switch tube M30 are both connected to the external power detection circuit 100. When the external power detection circuit 100 is connected to the control power supply VDD, the control end of the twenty-ninth switch tube M29 and the control end of the thirtieth switch tube M30 are at a high level.

[0133] The current input end of the twenty-ninth switch tube M29 is connected to the current output end of the twenty-seventh switch tube M27, and the current output end of the twenty-ninth switch tube M29 is grounded; the current input end of the thirtieth switch tube M30 is connected to the current output end of the twenty-eighth switch tube M28, and the current output end of the thirtieth switch tube M30 is grounded.

[0134] In this embodiment, when the external power detection circuit 100 is connected to the control power supply VDD, the control terminals of the twenty-ninth switch M29 and the thirtieth switch M30 are both at a high level. For example, as shown in FIG3 , the gate of the first switch M1 serves as point F, and the control terminals of the twenty-ninth switch M29 and the thirtieth switch M30 can be connected to point F. A circuit structure of a power supply with a wide output voltage range is shown in FIG7 , in which the external power detection circuit 100, the first voltage generation circuit 200, and the second voltage generation circuit 300 can share a common ground.

[0135] When the external power detection circuit 100 is connected to the control power supply VDD, the current I1 generated by the current source B1 can increase the voltage at the control terminal of the twenty-ninth switch tube M29 and the control terminal of the thirtieth switch tube M30, thereby turning on the twenty-ninth switch tube M29 and the thirtieth switch tube M30. When the twenty-seventh switch tube M27 and the twenty-eighth switch tube M28 are turned on, the second voltage generating circuit 300 can operate normally.

[0136] The twenty-ninth switch M29 and the thirtieth switch M30 generate a constant mirror current based on the current source B1. This mirror current maintains the control current flowing through the second voltage generation circuit 300 in a controllable state, thereby ensuring controllable power consumption of the second voltage generation circuit 300. Furthermore, in the second voltage generation circuit 300, the other switch transistors in the branch containing the twenty-ninth switch M29 and the thirtieth switch M30 all operate in a linear resistance region (e.g., the twenty-seventh switch M27 and the twenty-eighth switch M28). This means that the drain-source voltage difference (Vds) of the other switch transistors is relatively small. Furthermore, because the voltage across the sixth resistor R6 and the Zener diode Z1 is clamped, when the power supply VIN changes, the drain-source voltage difference between the twenty-ninth switch M29 and the thirtieth switch M30 can follow the change in the power supply VIN, ensuring reliable circuit operation.

[0137] The present application also provides a semiconductor integrated circuit control chip, which includes any of the power supplies with a wide output voltage range provided in the above embodiments. The power supply with a wide output voltage range can provide the required voltage to the internal modules of the chip.

[0138] The present application also provides a switching power supply circuit including the semiconductor integrated circuit control chip described above. The switching power supply circuit can be applied to various scenarios, for example, the switching power supply circuit can be used for battery charging.

[0139] Although the embodiments of the present application have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. A power supply with a wide output voltage range, characterized in that: include: An external power supply detection circuit (100), a first voltage generating circuit (200) and a second voltage generating circuit (300); The external power supply detection circuit (100) is powered by a control power supply; an output end of the external power supply detection circuit (100) is connected to input ends of the first voltage generating circuit (200) and the second voltage generating circuit (300); The external power supply detection circuit (100) is configured to detect whether the external power supply meets the power supply requirements; when the external power supply meets the power supply requirements, the output end of the external power supply detection circuit (100) outputs a first control signal; when the external power supply does not meet the power supply requirements, the output end of the external power supply detection circuit (100) outputs a second control signal; The first voltage generating circuit (200) is configured to: output a voltage corresponding to the external power supply in response to the first control signal; The second voltage generating circuit (300) is configured to: convert the input power supply in response to the second control signal, and output the converted voltage; The external power supply detection circuit (100) comprises: a current source B1, a first switch tube M1, a second switch tube M2, a third switch tube M3, a fourth switch tube M4, a fifth switch tube M5, a sixth switch tube M6, a seventh switch tube M7, an eighth switch tube M8, a ninth switch tube M9, a tenth switch tube M10, a first resistor R1, a second resistor R2 and a first inverter A1; wherein the first switch tube M1, the second switch tube M2, the seventh switch tube M7, the eighth switch tube M8, the ninth switch tube M9 and the tenth switch tube M10 are NPN-type transistors or N-type field effect transistors; the third switch tube M3, the fourth switch tube M4, the fifth switch tube M5 and the sixth switch tube M6 are PNP-type transistors or P-type field effect transistors; The input end of the current source B1 is configured to be connected to the control power supply, and the output end of the current source B1 is connected to the current input end of the first switch tube M1; The control end of the first switch tube M1 and the control end of the second switch tube M2 are both connected to the current input end of the first switch tube M1; the current output end of the first switch tube M1 and the current output end of the second switch tube M2 are grounded; One end of the first resistor R1 is configured to be connected to the external power supply, and the other end is grounded through the second resistor R2; The current input ends of the third switch tube M3, the fourth switch tube M4, the fifth switch tube M5, and the sixth switch tube M6 are all configured to be connected to the control power supply; The control end of the third switch tube M3 and the control end of the fourth switch tube M4 are both connected to the current output end of the fourth switch tube M4; the current output end of the third switch tube M3 is connected to the current input end of the ninth switch tube M9, and the current output end of the fourth switch tube M4 is connected to the current input end of the seventh switch tube M7; The control end of the fifth switch tube M5 and the control end of the sixth switch tube M6 are both connected to the current output end of the fifth switch tube M5; the current output end of the fifth switch tube M5 is connected to the current input end of the eighth switch tube M8, the current output end of the sixth switch tube M6 is connected to the current input end of the tenth switch tube M10, and is connected to the input end of the first inverter A1; the output end of the first inverter A1 serves as the output end of the external power detection circuit (100); The control end of the seventh switch tube M7 is configured to be connected to the first reference voltage, and the control end of the eighth switch tube M8 is connected to the end of the first resistor R1 close to the second resistor R2; the current output end of the seventh switch tube M7 and the current output end of the eighth switch tube M8 are both connected to the current input end of the second switch tube M2; The control end of the ninth switch tube M9 and the control end of the tenth switch tube M10 are both connected to the current input end of the ninth switch tube M9; the current output end of the ninth switch tube M9 and the current output end of the tenth switch tube M10 are grounded.

2. The power supply according to claim 1, characterized in that: The external power supply detection circuit (100) further comprises: a first hysteresis circuit (101) and a second hysteresis circuit (102); the first hysteresis circuit (101) comprises: a third resistor R3 and an eleventh switch tube M11; the eleventh switch tube M11 is an NPN-type triode or an N-type field effect tube; One end of the third resistor R3 is connected to an end of the second resistor R2 away from the first resistor R1, and the other end of the third resistor R3 is grounded; The control end of the eleventh switch tube M11 is connected to the output end of the first inverter A1; the current input end of the eleventh switch tube M11 is connected to an end of the third resistor R3 close to the second resistor R2, and the current output end of the eleventh switch tube M11 is grounded; The second hysteresis circuit (102) is configured to provide a charging current flowing to the current input terminal of the tenth switch tube M10 when the output terminal of the first inverter A1 is at a low level.

3. The power supply according to claim 2, characterized in that: The second hysteresis circuit (102) comprises: a twelfth switch tube M12 and a thirteenth switch tube M13; the twelfth switch tube M12 and the thirteenth switch tube M13 are PNP type triodes or P type field effect tubes; The control end of the twelfth switch tube M12 is connected to the control end of the fifth switch tube M5, the current input end of the twelfth switch tube M12 is configured to be connected to the control power supply, and the current output end of the twelfth switch tube M12 is connected to the current input end of the thirteenth switch tube M13; The control end of the thirteenth switch tube M13 is connected to the output end of the first inverter A1 , and the current output end of the thirteenth switch tube M13 is connected to the current input end of the tenth switch tube M10 .

4. The power supply according to claim 1, characterized in that: The first voltage generating circuit (200) comprises: a response circuit (201) and a switch circuit (202); The input end of the response circuit (201) is connected to the output end of the external power detection circuit (100), and the output end of the response circuit (201) is connected to the control end of the switch circuit (202); the response circuit (201) is configured to convert the first control signal into a third control signal, and convert the second control signal into a fourth control signal; The input end of the switch circuit (202) is configured to be connected to the external power supply, and the output end of the switch circuit (202) serves as the output end of the first voltage generating circuit (200); the switch circuit (202) is configured such that when the third control signal is input to the control end of the switch circuit (202), the input end and the output end of the switch circuit (202) are turned on; when the fourth control signal is input to the control end of the switch circuit (202), the input end and the output end of the switch circuit (202) are turned off.

5. The power supply according to claim 4, characterized in that: The response circuit (201) comprises: a second inverter A2, a third inverter A3, a fourteenth switch tube M14, a fifteenth switch tube M15, a sixteenth switch tube M16 and a seventeenth switch tube M17; the fourteenth switch tube M14 and the fifteenth switch tube M15 are PNP-type triodes or P-type field effect tubes, and the sixteenth switch tube M16 and the seventeenth switch tube M17 are NPN-type triodes or N-type field effect tubes; The input end of the second inverter A2 is connected to the output end of the external power supply detection circuit (100), and the output end of the second inverter A2 is connected to the input end of the third inverter A3; The current input ends of the fourteenth switch tube M14 and the fifteenth switch tube M15 are connected to the output end of the first voltage generating circuit (200); the control end of the fourteenth switch tube M14 is connected to the current output end of the fifteenth switch tube M15, and the control end of the fifteenth switch tube M15 is connected to the current output end of the fourteenth switch tube M14; The control end of the sixteenth switch tube M16 is connected to the output end of the third inverter A3, the current input end of the sixteenth switch tube M16 is connected to the current output end of the fourteenth switch tube M14, and the current output end of the sixteenth switch tube M16 is grounded; the current output end of the fourteenth switch tube M14 is also connected to the control end of the switch circuit (202); The control end of the seventeenth switch tube M17 is connected to the output end of the second inverter A2, the current input end of the seventeenth switch tube M17 is connected to the current output end of the fifteenth switch tube M15, and the current output end of the seventeenth switch tube M17 is grounded; And / or, the switch circuit (202) comprises: a fourth inverter A4 and an eighteenth switch tube M18; the eighteenth switch tube M18 is a P-type field effect tube; The input end of the fourth inverter A4 is connected to the output end of the response circuit (201), and the output end of the fourth inverter A4 is connected to the control end of the eighteenth switch tube M18; The drain of the eighteenth switch tube M18 is configured to be connected to the external power supply, and the source of the eighteenth switch tube M18 serves as the output end of the first voltage generating circuit (200).

6. The power supply according to claim 1, characterized in that: The second voltage generating circuit (300) comprises: a power supply switch tube M0, a fourth resistor R4, a fifth resistor R5, a nineteenth switch tube M19, a twentieth switch tube M20, a twenty-first switch tube M21, a twenty-second switch tube M22, a twenty-third switch tube M23, a twenty-fourth switch tube M24, a twenty-fifth switch tube M25, a twenty-sixth switch tube M26, a twenty-seventh switch tube M27 and a twenty-eighth switch tube M28; wherein the nineteenth switch tube M19, the twenty-tenth switch tube M20, the twenty-first switch tube M21 and the twenty-second switch tube M22 are PNP type transistors or P type field effect transistors; the twenty-third switch tube M23, the twenty-fourth switch tube M24, the twenty-fifth switch tube M25, the twenty-sixth switch tube M26, the twenty-seventh switch tube M27 and the twenty-eighth switch tube M28 are NPN type transistors or N type field effect transistors; The current input end of the power switch tube M0 is configured to be connected to the power supply, and the current output end of the power switch tube M0 serves as the output end of the second voltage generating circuit (300); One end of the fourth resistor R4 is connected to the current output end of the power switch tube M0, and the other end is grounded through the fifth resistor R5; The current input ends of the nineteenth switch tube M19, the twentieth switch tube M20, the twenty-first switch tube M21, and the twenty-second switch tube M22 are all configured to be connected to the power supply; The control end of the nineteenth switch tube M19 and the control end of the twentieth switch tube M20 are both connected to the current output end of the twentieth switch tube M20; the current output end of the nineteenth switch tube M19 is connected to the current input end of the twenty-third switch tube M23, and the current output end of the twentieth switch tube M20 is connected to the current input end of the twenty-fifth switch tube M25; The control end of the twenty-first switch tube M21 and the control end of the twenty-second switch tube M22 are both connected to the current output end of the twenty-first switch tube M21; the current output end of the twenty-first switch tube M21 is connected to the current input end of the twenty-sixth switch tube M26, and the current output end of the twenty-second switch tube M22 is connected to the current input end of the twenty-fourth switch tube M24 and connected to the control end of the power supply switch tube M0; The control end of the twenty-third switch tube M23 and the control end of the twenty-fourth switch tube M24 are both connected to the current input end of the twenty-third switch tube M23; the current output end of the twenty-third switch tube M23 and the current output end of the twenty-fourth switch tube M24 are both connected to the current input end of the twenty-seventh switch tube M27; The control end of the twenty-fifth switch tube M25 is configured to be connected to the second reference voltage, and the control end of the twenty-sixth switch tube M26 is connected to the end of the fourth resistor R4 close to the fifth resistor R5; the current output end of the twenty-fifth switch tube M25 and the current output end of the twenty-sixth switch tube M26 are both connected to the current input end of the twenty-eighth switch tube M28; The control end of the twenty-seventh switch tube M27 and the control end of the twenty-eighth switch tube M28 are both connected to the output end of the external power detection circuit (100); the current output end of the twenty-seventh switch tube M27 and the current output end of the twenty-eighth switch tube M28 are grounded.

7. The power supply according to claim 6, characterized in that: The second voltage generating circuit (300) further comprises: a voltage stabilizing diode Z1 and a sixth resistor R6; the voltage stabilizing diode Z1 and the sixth resistor R6 are connected in series and arranged between the current input end of the nineteenth switch tube M19 and the current output end of the twenty-third switch tube M23; And / or, the second voltage generating circuit (300) further comprises: a twenty-ninth switch tube M29 and a thirtieth switch tube M30; the twenty-ninth switch tube M29 and the thirtieth switch tube M30 are NPN-type triodes or N-type field effect tubes; The control end of the twenty-ninth switch tube M29 and the control end of the thirtieth switch tube M30 are both connected to the external power detection circuit (100), and when the external power detection circuit (100) is connected to the control power supply, the control end of the twenty-ninth switch tube M29 and the control end of the thirtieth switch tube M30 are at a high level; The current input end of the twenty-ninth switch tube M29 is connected to the current output end of the twenty-seventh switch tube M27, and the current output end of the twenty-ninth switch tube M29 is grounded; The current input end of the 30th switch tube M30 is connected to the current output end of the 28th switch tube M28, and the current output end of the 30th switch tube M30 is grounded.

8. A semiconductor integrated circuit control chip, characterized in that: A power supply with a wide output voltage range comprising the power supply of any one of claims 1 to 7.

9. A switching power supply circuit, characterized in that: Comprising the semiconductor integrated circuit control chip as claimed in claim 8.

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