Linear voltage stabilization source, chip and electronic equipment

Abstract

The invention provides a linear voltage stabilization source, a chip and electronic equipment, and the system comprises a voltage stabilization adjustment module which receives an input power supply and converts the input power supply into a stable output power supply through the adjustment of a power tube in the voltage stabilization adjustment module, and the output power supply is smaller than the input power supply; and the power supply voltage detection module is connected with the input power supply, detects the input power supply, and outputs a turn-off control signal of the voltage stabilization adjustment module when the input power supply shakes based on a detection result. According to the linear voltage stabilization source, the chip and the electronic equipment, the power supply detection module is introduced, when the input power supply rapidly jitters, the grid voltage of the power tube is pulled down to close the power tube, a transmission path of the input power supply to the output power supply is cut off, and protection of an electric circuit is achieved; and after the input power supply is recovered to be stable, the power tube is restarted to supply power to the electric circuit. According to the invention, the risk that the power utilization circuit is damaged can be effectively reduced, and the safety of the chip and the electronic equipment is improved.

Description

Technical Field

[0001] The present invention relates to the field of power supplies, and in particular to a linear voltage regulator, a chip and an electronic device. Background Art

[0002] Electronic devices generally obtain power through two ways: one is from AC power after rectification, and the other is from batteries. No matter which one provides power supply voltage, the electronic device will vary in a large range when working; in order to ensure the stability of the power supply, a voltage stabilizer is required. However, when the input power of the voltage stabilizer fluctuates greatly in a short period of time, its output power supply will still fluctuate; when the power supply becomes abnormally high, it is easy to cause the subsequent power circuit to be broken down, causing chip damage.

[0003] Therefore, how to avoid the influence of input power jitter on the output power of the regulator and protect the power circuit has become one of the problems that technical personnel in this field need to solve urgently.

[0004] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a linear voltage regulator, a chip and an electronic device for solving the problem in the prior art that input power jitter may damage the power circuit.

[0006] In order to achieve the above-mentioned object and other related objects, the present invention provides a linear voltage regulator, which at least includes:

[0007] Voltage regulation module and power supply voltage detection module;

[0008] The voltage regulating and adjusting module receives an input power supply, and converts the input power supply into a stable output power supply by adjusting the power tube in the voltage regulating and adjusting module, and the output power supply is smaller than the input power supply;

[0009] The power supply voltage detection module is connected to the input power supply, detects the input power supply, and outputs a shutdown control signal of the voltage regulation and adjustment module when the input power supply jitters based on the detection result.

[0010] Optionally, the voltage regulation module includes a power tube, a feedback unit and an error amplifier;

[0011] The first end of the power tube is connected to the input power supply, the second end is grounded via the feedback unit, and the control end is connected to the output end of the error amplifier and the power supply voltage detection module; the second end of the power tube outputs the output power supply;

[0012] The first input terminal of the error amplifier is connected to the feedback voltage output by the feedback unit, and the second input terminal is connected to the reference voltage. The error amplifier generates a control signal for the power tube based on the difference between the feedback voltage and the reference voltage.

[0013] More optionally, the power tube is an NMOS tube.

[0014] More optionally, the feedback unit includes a first resistor and a second resistor connected in series between the second end of the power tube and ground; a connection node between the first resistor and the second resistor serves as an output end of the feedback unit.

[0015] More optionally, the non-phase input terminal of the error amplifier is connected to the reference voltage, the inverting input terminal is connected to the output terminal of the feedback unit, and the output terminal is connected to the control terminal of the power tube.

[0016] More optionally, the power supply voltage detection module includes a capacitor, a first transistor, a second transistor and a Zener transistor;

[0017] One end of the capacitor is connected to the input power supply, and the other end is connected to the cathode of the Zener tube; the anode of the Zener tube is grounded;

[0018] The first end of the first transistor is connected to the cathode of the Zener tube, the second end is grounded, and the control end receives a bias voltage; and is used to provide a pull-down current;

[0019] The first end of the second transistor is connected to the control end of the power tube, the second end is grounded, and the control end is connected to the cathode of the Zener tube; when the input power supply is stable, the second transistor is turned off, and when the input power supply jitters, the second transistor is turned on to turn off the power tube.

[0020] More optionally, the first transistor is an NMOS transistor, and the second transistor is an NMOS transistor.

[0021] To achieve the above-mentioned purpose and other related purposes, the present invention also provides a chip, which at least includes: the above-mentioned linear voltage regulator and a power circuit; the linear voltage regulator supplies power to the power circuit.

[0022] Optionally, the chip further includes a power supply circuit, and the power supply module provides input power for the linear voltage regulator; the power supply module is a rectifier circuit or a battery.

[0023] In order to achieve the above-mentioned object and other related objects, the present invention further provides an electronic device, which at least includes: the above-mentioned linear voltage regulator.

[0024] As described above, the linear voltage regulator, chip and electronic device of the present invention have the following beneficial effects:

[0025] The linear voltage regulator, chip and electronic device of the present invention introduce a power detection module, and when the input power source has a rapid jitter, the gate voltage of the power tube is pulled down to turn off the power tube, cutting off the transmission path of the input power source to the output power source, thereby protecting the power circuit; and after the input power source is restored to stability, the power tube is turned on again to supply power to the power circuit. The present invention can effectively reduce the risk of damage to the power circuit and improve the safety of the chip and electronic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Shown is a structural schematic diagram of a low-dropout linear regulator.

[0027] Figure 2 Shown is a block diagram of a linear voltage regulator of the present invention.

[0028] Figure 3 Shown is a schematic structural diagram of the linear voltage regulator of the present invention.

[0029] Figure 4 The figure shows the simulation waveform of a linear voltage regulator without adding a power detection circuit.

[0030] Figure 5 Shown is a schematic diagram of simulation waveforms of a linear voltage regulator with a power detection circuit added to the present invention.

[0031] Component number description

[0032] 1 Low Dropout Linear Regulator

[0033] 2 Linear voltage regulator

[0034] 21 Voltage regulation module

[0035] 211 Feedback Unit

[0036] 212 Error amplifier

[0037] 22 Power supply voltage detection module DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0039] See also Figure 1 to Figure 5 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0040] like Figure 1 The figure shows a low voltage drop linear regulator 1, which converts the battery voltage V BAT Converted to supply voltage V CC ; Among them, the feedback module is for the supply voltage V CC Sampling and feedback voltage V F Provided to the error amplifier; the error amplifier calculates the feedback voltage V F With reference voltage V REF Based on the "virtual short" at the input of the error amplifier, the power tube is continuously adjusted so that the feedback voltage VF is stabilized at the reference voltage V REF , and then get a stable supply voltage V CC ; By adjusting the feedback voltage V F With the supply voltage V CC The ratio of can get the appropriate supply voltage V CC .

[0041] When the battery voltage V BAT When large jitter occurs in a short time, the supply voltage V CC In a short time, it follows the battery voltage V BAT Increase, in extreme cases, the supply voltage V CC It may more than double; at this time, the supply voltage V CC The maximum withstand voltage of the subsequent low-voltage circuit may be approached or exceeded, increasing the risk of chip breakdown due to overvoltage.

[0042] In order to solve the above problems, the present invention provides a linear voltage regulator, which shuts down the linear voltage regulator when the input power has a large jitter in a short time, preventing the output power from increasing, thereby reducing the risk of subsequent power circuits (low voltage) being damaged.

[0043] like Figure 2 and Figure 3 As shown, the linear voltage regulator 2 of the present invention includes:

[0044] A voltage regulating module 21 and a power supply voltage detecting module 22 .

[0045] like Figure 2 As shown, the voltage regulating and adjusting module 21 receives the input power Vin (provided by a battery or a rectifier module as an example), and converts the input power Vin into a stable output power Vout by adjusting the power tube Q in the voltage regulating and adjusting module 21; the output power Vout is less than the input power Vin.

[0046] Specifically, the input power supply of the voltage regulating module 21 is higher than the output power supply by a certain voltage difference. In this embodiment, the voltage difference is the minimum voltage difference for the voltage regulating module 21 to work normally and maintain a stable output. Any circuit structure that can achieve low voltage difference linear voltage regulation is applicable to the voltage regulating module 21 of the present invention. Figure 2 and Figure 3 As shown, as an example, the voltage regulation and adjustment module 21 includes a power tube Q, a feedback unit 211 and an error amplifier 212. The first end of the power tube Q is connected to the input power supply Vin, the second end is connected to the feedback unit 211, and the control end is connected to the output end of the error amplifier 212; the power tube Q is controlled based on the output signal of the error amplifier 212, so as to adjust the output voltage of the power tube Q to achieve the purpose of voltage regulation. In this example, the power tube Q is implemented by an NMOS tube, then the first end of the power tube Q is the drain, the second end is the source, and the control end is the gate; in actual use, the power tube Q can use any power device suitable for the application of the present invention, including but not limited to PNP transistors, NPN transistors, PMOS tubes, which are not described one by one here. One end of the feedback unit 211 is connected to the second end of the power tube Q, and the other end is grounded; the output power supply Vout is sampled, and the feedback voltage VF is output. In this embodiment, the feedback unit 211 includes a first resistor R1 and a second resistor R2 connected in series; the first end of the first resistor R1 is connected to the second end of the power tube Q, and the second end is connected to the first end of the second resistor R2 and serves as the output end of the feedback unit 211; the second end of the second resistor R2 is grounded; the first resistor R1 and the second resistor R2 can be a single resistor, or a series, parallel or series-parallel structure of multiple resistors; in actual use, any circuit structure that can sample the output power supply Vout and generate a corresponding feedback voltage is applicable to the present invention, and will not be described in detail here. The first input end of the error amplifier 212 is connected to the feedback voltage VF, and the second input end is connected to the reference voltage V REF , based on the difference between the feedback voltage VF and the reference voltage VREF, a control signal of the power tube Q is generated. As an example, the non-inverting input terminal of the error amplifier 212 is connected to the reference voltage V REF, the inverting input terminal is connected to the feedback voltage V F , the output end is connected to the control end of the power tube Q; in actual use, the corresponding relationship between the input signal and the input polarity of the error amplifier 212 can be interchanged, and the polarity of each node can be adjusted by devices such as inverters, which can realize the logic of the present invention, and will not be described in detail here.

[0047] Specifically, the output power Vout should be stable at a preset voltage value. When the output power Vout increases, the feedback voltage V F When the output power Vout decreases, the feedback voltage VF decreases accordingly and is less than the reference voltage V REF , the driving current output by the error amplifier 212 increases, the voltage drop of the power tube Q decreases, and the output power supply Vout increases; this cycle repeats until a stable output is finally obtained.

[0048] like Figure 2 As shown, the power supply voltage detection module 22 is connected to the input power supply Vin, detects the input power supply Vin, and outputs a shutdown control signal of the voltage regulation and adjustment module 21 when the input power supply Vin jitters based on the detection result.

[0049] Specifically, the power supply voltage detection module 22 determines whether the input power supply Vin is jittering by detecting the amplitude of the input power supply Vin. The judgment threshold can be set according to actual needs (that is, when the amplitude of the input power supply Vin is greater than the set value, and the difference is greater than the threshold, it is determined that there is a jitter that risks damaging subsequent power circuits; when the difference does not reach the threshold, it is determined that there is no jitter that risks damaging subsequent power circuits). When it is determined that the input power supply Vin is jittering, a shutdown control signal for the power tube Q is generated, and the power tube Q is then shut down; when it is determined that the input power supply Vin is not jittering, there is no output signal, which does not affect the control of the error amplifier 212 on the power tube Q, and the voltage regulation adjustment module 21 works normally and outputs a stable output power supply Vout. Any circuit structure that can achieve the above functions is suitable for the present invention.

[0050] More specifically, if Figure 3As shown, as an example, the power supply voltage detection module 22 includes a capacitor C, a first transistor M1, a second transistor M2 and a Zener tube Z. One end of the capacitor C is connected to the input power supply Vin, and the other end is connected to the cathode of the Zener tube Z; the anode of the Zener tube Z is grounded, and the capacitor C and the Zener tube Z are used to sense the increase of the input power supply Vin in a short time. The first end of the first transistor M1 is connected to the cathode of the Zener tube Z, the second end is grounded, and the control end receives the bias voltage Vb; it is used to provide a pull-down current. The first end of the second transistor M2 is connected to the control end of the power tube Q, the second end is grounded, and the control end is connected to the cathode of the Zener tube Z; that is, based on the voltage change sensed by the capacitor C and the pull-down current provided by the first transistor M1, the control of the second transistor M2 is realized (the Zener tube Z is used to clamp the control end of the power tube Q). In this example, the first transistor M1 and the second transistor M2 are both implemented by NMOS tubes, and in actual use, the functions of the power supply voltage detection module 22 of the present invention can be realized, including but not limited to PMOS tubes, which are not repeated here.

[0051] It should be noted that, as an example, the power tube Q of the present invention is manufactured by a high voltage process. In actual use, the power tube Q, the first transistor M1 and the second transistor M2 can be configured according to actual needs and are not limited to this embodiment.

[0052] More specifically, in this embodiment, the first transistor M1 is controlled by the bias voltage Vb to provide a pull-down current; when the input power supply Vin is stable (no jitter that may damage the subsequent power circuit), the voltage across the capacitor C does not change, and the pull-down current provided by the first transistor M1 pulls the gate of the second transistor M2 down to the ground, the second transistor M2 is turned off, and no current flows through the second transistor M2, that is, the power supply voltage detection module 22 has no output signal, and the power tube Q is controlled by the output signal of the error amplifier 212. When the input power supply Vin increases rapidly (there is jitter that may damage the subsequent power circuit), the input power supply Vin charges the capacitor C, and the faster the input power supply Vin changes, the greater the charging current of the capacitor C (at this time, the pull-down current is much smaller than the charging current of the capacitor C), and the more charge is transmitted to the gate of the second transistor M2 through the capacitor C, so that the gate voltage V G2 The second transistor M2 is turned on and the gate voltage V G1 Pulled down to ground, the power tube Q is turned off, and the output power Vout is reduced to 0, thereby protecting the subsequent power circuits; after the input power Vin is stable, under the action of the first transistor M1, the gate voltage of the second transistor M2 is pulled down again, the voltage regulation module 21 starts working again, and the output power Vout rises to the preset value.

[0053] like Figure 4The figure shows the simulation waveform of the linear voltage regulator 2 without adding the power detection circuit. It can be seen from the figure that the input power Vin changes rapidly at 500μs, rising from 13.5V to 40V within 0.1μs; at this time, the output power Vout changes accordingly, rising by 2.2V. Figure 5 The figure shows the simulation waveform of the linear voltage regulator 2 with the power detection circuit added. It can be seen from the figure that the input power Vin rises from 13.5V to 40V within 0.1μs, and the gate voltage V G2 becomes high, and under the action of the second transistor M2, the gate voltage of the power tube Q is pulled down, thereby turning off the power tube Q. At this time, the output power supply Vout becomes 0, and after the input power supply Vin is stable, the output power supply Vout returns to its original value.

[0054] The present invention also provides a chip, which at least includes: a linear voltage regulator 2 of the present invention and a power circuit; the linear voltage regulator 2 supplies power to the power circuit. As an example, the chip also includes a power supply circuit, and the power supply module provides an input power Vin for the linear voltage regulator 2; the power supply module includes but is not limited to a rectifier circuit or a battery. In the chip of the present invention, when the input power Vin fluctuates rapidly, the linear voltage regulator 2 is turned off, which can prevent the output power Vout (power supply of the power circuit) from increasing, reduce the risk of damage to the power circuit, and improve the safety of the chip.

[0055] The present invention further provides an electronic device, which at least comprises: the linear voltage regulator 2 of the present invention. The electronic device includes but is not limited to consumer electronics, industrial control electronics, communication electronics, etc., which are not described in detail here.

[0056] In summary, the present invention provides a linear voltage regulator, chip and electronic device, including: a voltage regulator adjustment module and a power supply voltage detection module; the voltage regulator adjustment module receives the input power supply, and converts the input power supply into a stable output power supply by adjusting the power tube in the voltage regulator adjustment module, and the output power supply is less than the input power supply; the power supply voltage detection module is connected to the input power supply, detects the input power supply, and outputs a shutdown control signal of the voltage regulator adjustment module when the input power supply jitters based on the detection result. The linear voltage regulator, chip and electronic device of the present invention introduce a power supply detection module, and when the input power supply jitters rapidly, the gate voltage of the power tube is pulled down to turn off the power tube, cut off the transmission path of the input power supply to the output power supply, and realize the protection of the power circuit; and after the input power supply is restored to stability, the power tube is reopened to realize the power supply to the power circuit. The present invention can effectively reduce the risk of damage to the power circuit and improve the safety of chips and electronic devices. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A linear voltage regulator, characterized in that: The linear voltage regulator source at least comprises: Voltage regulation module and power supply voltage detection module; The voltage regulating and adjusting module receives an input power supply, and converts the input power supply into a stable output power supply by adjusting the power tube in the voltage regulating and adjusting module, and the output power supply is smaller than the input power supply; The power supply voltage detection module is connected to the input power supply, detects the input power supply, and outputs a shutdown control signal of the voltage regulation and adjustment module when the input power supply jitters based on the detection result.

2. The linear voltage regulator according to claim 1, characterized in that: The voltage regulation module includes a power tube, a feedback unit and an error amplifier; The first end of the power tube is connected to the input power supply, the second end is grounded via the feedback unit, and the control end is connected to the output end of the error amplifier and the power supply voltage detection module; the second end of the power tube outputs the output power supply; The first input terminal of the error amplifier is connected to the feedback voltage output by the feedback unit, and the second input terminal is connected to the reference voltage. The error amplifier generates a control signal for the power tube based on the difference between the feedback voltage and the reference voltage.

3. The linear voltage regulator according to claim 2, characterized in that: The power tube is an NMOS tube.

4. The linear voltage regulator according to claim 2, characterized in that: The feedback unit includes a first resistor and a second resistor connected in series between the second end of the power tube and the ground; a connection node between the first resistor and the second resistor serves as an output end of the feedback unit.

5. The linear voltage regulator according to claim 2, characterized in that: The non-phase input terminal of the error amplifier is connected to the reference voltage, the inverting input terminal is connected to the output terminal of the feedback unit, and the output terminal is connected to the control terminal of the power tube.

6. The linear voltage regulator according to any one of claims 1 to 5, characterized in that: The power supply voltage detection module includes a capacitor, a first transistor, a second transistor and a Zener transistor; One end of the capacitor is connected to the input power supply, and the other end is connected to the cathode of the Zener tube; the anode of the Zener tube is grounded; The first end of the first transistor is connected to the cathode of the Zener tube, the second end is grounded, and the control end receives a bias voltage; Used to provide pull-down current; The first end of the second transistor is connected to the control end of the power tube, the second end is grounded, and the control end is connected to the cathode of the Zener tube; when the input power supply is stable, the second transistor is turned off, and when the input power supply jitters, the second transistor is turned on to turn off the power tube.

7. The linear voltage regulator according to claim 6, characterized in that: The first transistor is an NMOS transistor, and the second transistor is an NMOS transistor.

8. A chip, characterized in that: The chip at least comprises: a linear voltage regulator and a power circuit as described in any one of claims 1 to 7; the linear voltage regulator supplies power to the power circuit.

9. The chip according to claim 8, characterized in that: The chip also includes a power supply circuit, and the power supply module provides input power for the linear voltage regulator; the power supply module is a rectifier circuit or a battery.

10. An electronic device, characterized in that: The electronic device at least comprises: a linear voltage regulator as described in any one of claims 1-7.

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