Power management circuit and electronic device

Abstract

A power management circuit provided by the present invention includes: a constant current regulation mirror unit, a single-wire communication control unit, a current detection resistor unit, an operational amplifier unit, and a target pin; a first end of the current detection resistor unit is grounded; a second end of the current detection resistor unit is used to connect to the target pin; and the target pin is further connected to a first input end of the single-wire communication control unit, a first end of the constant current regulation mirror unit, and an inverting input end of the operational amplifier unit; a first output end of the single-wire communication control unit is connected to a non-inverting input end of the operational amplifier unit, and an output end of the operational amplifier unit is connected to a second end of the constant current regulation mirror unit; a second output end of the single-wire communication control unit is connected to a third end of the constant current regulation mirror unit; the target pin is used to connect to an IO port of a processor; the constant current regulation mirror unit further includes a voltage input end and a voltage output end, and the voltage output end is used to supply power to an external electronic device. The present invention realizes current detection and low-power shutdown of the constant current regulation mirror unit with only one IO port.

Description

Technical Field

[0001] The present invention relates to the field of circuits, and in particular to a power management circuit and an electronic device. Background Art

[0002] Currently, in the application environments of various power path management chips, the basic functions required by customers for chip products are to turn on and off the power switch of the path. Considering the needs of safety and reliability and system-level applications, functions such as configurable constant current points and the ability to detect the current value flowing through the power path are also desired. However, in the final implementation, it is also hoped to minimize the occupation of the IO port resources of the supporting processor and achieve the overall low power consumption of the system as much as possible.

[0003] In the prior art, two IO ports of the processor are required to implement current detection, path on / off control, and low-power processing. Summary of the Invention

[0004] The present invention provides a control circuit and an electronic device to achieve the on / off of the power path and the current detection function using only one IO port.

[0005] According to a first aspect of the present invention, a power management circuit is provided, including: a constant current regulation mirror unit, a single-wire communication control unit, a current detection resistor unit, an operational amplifier unit, and a target pin;

[0006] The first end of the current detection resistor unit is grounded; the second end of the current detection resistor unit is used to connect to the target pin; and the target pin is also connected to the first input end of the single-wire communication control unit, the first end of the constant current regulation mirror unit, and the inverting input end of the operational amplifier unit; the first output end of the single-wire communication control unit is connected to the non-inverting input end of the operational amplifier unit, the output end of the operational amplifier unit is connected to the second end of the constant current regulation mirror unit; the second output end of the single-wire communication control unit is connected to the third end of the constant current regulation mirror unit; the target pin is used to connect to the IO port of the processor; the constant current regulation mirror unit further includes a voltage input end and a voltage output end, and the voltage output end is used to supply power to the external electronic device;

[0007] Wherein, the operational amplifier unit is configured to: after the second end of the current detection resistor unit is connected to the target pin and a loop is formed between the voltage output end and the external electronic device, control the path between the voltage input end and the voltage output end of the constant current regulation mirror unit to be turned on, and maintain the current output from the voltage output end at the constant current point; and after the path is turned on, the current output from the voltage output end is proportional to the current flowing through the current detection resistor unit;

[0008] The single-wire communication control unit is configured to:

[0009] Control the shutdown of the constant current regulation mirror unit according to a first external control command input through the connected IO port.

[0010] Optionally, the controlling the shutdown of the constant current regulation mirror unit according to a first external control command input through the connected IO port includes:

[0011] Receive the first external control command input through the IO port;

[0012] If the first external control command matches a preset control command in the single-wire communication control unit, then control the constant current regulation mirror unit to shut down.

[0013] Optionally, the first external control command is represented by a first digital command composed of at least one logical bit; the preset control command is represented by a second digital command composed of at least one logical bit.

[0014] Optionally, the single-wire communication control unit is further configured to:

[0015] Configure a first reference voltage at the non-inverting input terminal of the operational amplifier unit according to a second external control command input through the connected IO port, so as to adjust the constant current point of the current output from the voltage output terminal of the constant current regulation mirror unit.

[0016] Optionally, the configuring a first reference voltage at the non-inverting input terminal of the operational amplifier unit according to a second external control command input through the connected IO port, so as to adjust the constant current point of the current output from the voltage output terminal of the constant current regulation mirror unit includes:

[0017] Receive the second external control command input through the IO port;

[0018] If the second external control command matches a preset configuration command in the single-wire communication control unit, then adjust the constant current point of the current output from the voltage output terminal of the constant current regulation mirror unit, and the preset configuration command is represented by different values of the first reference voltage.

[0019] Optionally, the second external control command is represented by a third digital command composed of at least one logical bit; the preset configuration command is represented by a fourth digital command composed of at least one logical bit, and different fourth digital commands correspond to different values of the first reference voltage.

[0020] Optionally, the constant current point is N times the first reference voltage divided by the resistance value of the current detection resistor unit, where N is a positive number.

[0021] Optionally, the current detection resistor unit includes an internal current detection resistor and a switch unit. The first end of the internal current detection resistor is connected to the first end of the switch unit. The second end of the switch unit is grounded. The control end of the switch unit is connected to the third output end of the single-wire communication control unit. The second end of the internal current detection resistor is used to connect to the target pin.

[0022] Optionally, the current detection resistor unit includes an external current detection resistor. The first end of the external current detection resistor is grounded. The second end of the external current detection resistor is used to connect to the target pin.

[0023] Optionally, the power management circuit further includes a trigger unit. The non-inverting input end of the trigger unit is connected to the target pin. The inverting input end of the trigger unit is used to input a second reference voltage. The output end of the trigger unit is connected to the fourth end of the constant current mirror adjustment unit.

[0024] The trigger unit is configured to: when the voltage of the IO port connected to the target pin is greater than the second reference voltage, form a turn-off voltage at the output end to turn off the path between the voltage input end and the voltage output end of the constant current mirror adjustment unit.

[0025] Optionally, the operational amplifier unit includes an amplifier, and the trigger unit includes a comparator.

[0026] The electronic device provided according to the second aspect of the present invention includes the above-mentioned power management circuit and the processor.

[0027] The power management circuit and the electronic device provided by the present invention can, through the cooperation of the single-wire communication control unit and each circuit unit, realize the turn-off of the constant current adjustment mirror unit and the detection of the current output from the voltage output end only through one IO port, avoiding the need to design two IO ports in the prior art to realize the turn-off of the constant current adjustment mirror unit and current detection. Further, through the use of the single-wire communication control unit, the present invention can maintain the target pin at a low level when turning off the constant current adjustment mirror unit, thereby avoiding leakage current on the current detection resistor unit when the target pin is at a high level, and thus realizing low-power turn-off.

[0028] In addition, as a further preferred method, the power management circuit provided by the present invention can also adjust the first reference voltage input to the operational amplifier unit through the single-wire communication control unit, thereby realizing the adjustable constant current point.

[0029] And in the preferred embodiment, the present invention also integrates the current detection resistor unit into the chip as an internal current detection resistor, thereby saving the use of external components, reducing the soldering cost of the circuit and the area of the system circuit board occupied by the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 is a schematic structural diagram of a power management circuit different from the embodiment of the present invention;

[0032] Figure 2 is a schematic structure of the power management circuit in an embodiment of the present invention Figure 1 ;

[0033] Figure 3 is a schematic structural diagram of the power management circuit in an application scenario of the present invention;

[0034] Figure 4 is a schematic structure of the power management circuit in an embodiment of the present invention Figure 2 ;

[0035] Figure 5 is a schematic structure of the power management circuit in an embodiment of the present invention Figure 3 .

[0036] DESCRIPTION OF REFERENCE NUMERALS:

[0037] 1 - Constant current regulation mirror unit;

[0038] 2 - Single - wire communication control unit;

[0039] 3 - Current detection resistor unit;

[0040] 31 - Built - in current detection resistor;

[0041] 32 - Switch unit;

[0042] 33 - External current detection resistor;

[0043] 4 - Operational amplifier unit;

[0044] 5 - Target pin;

[0045] 6 - Trigger unit. DETAILED DESCRIPTION OF THE INVENTION

[0046] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above accompanying drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0048] The technical solutions of the present invention will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0049] Before filing this application, the applicant conducted a full study on the power management circuit and proposed based on the study Figure 1 the power management circuit shown. For Figure 1 the power management circuit shown, currently, two IO ports are required to implement the current detection and low-power shutdown functions. Specifically, as Figure 1 shown, the power management circuit includes: a constant current regulation mirror unit 1, an external current detection resistor 33, an operational amplifier unit 4, a target pin 5, and a trigger unit 6;

[0050] The first end of the external current detection resistor 33 is connected to the first IO port of the processor, and the second end of the external current detection resistor 33 is used to connect to the target pin 5; and the target pin 5 is also connected to the inverting input terminal of the operational amplifier unit 4 and the non-inverting input terminal of the trigger unit 6; the output terminal of the operational amplifier unit 4 is connected to the first end of the constant current regulation mirror unit 1, and the output terminal of the trigger unit 6 is connected to the second end of the constant current regulation mirror unit 1; the target pin 5 is used to connect to the second IO port of the processor; the constant current regulation mirror unit 1 further includes a voltage input terminal VIN and a voltage output terminal VOUT, and the voltage output terminal VOUT is used to supply power to an external electronic device.

[0051] Please continue to refer toFigure 1 , to achieve low-power operation, Figure 1 For the solution shown, two IOs of an external processor are required, which are respectively connected to ILMDIS (i.e., the target pin 5) and the ON-OFF IO pin (i.e., the first end of the external current sensing resistor 33). The current detection of the VIN to VOUT channel and the on / off control of the power path are respectively achieved through the two pins.

[0052] Specifically, Figure 1 In the solution shown, when the ON-OFF IO is grounded, the ILMDIS pin (i.e., the target pin 5) is connected to the ADCIO (the first IO port) of the external processor, and the voltage of the ILMDIS pin (i.e., the target pin 5) can be read to obtain the Isense current, and then the Iout current (i.e., the current of the voltage output terminal VOUT) can be detected (Iout = n * Isense).

[0053] In addition, to achieve low power consumption when the power path from VIN to VOUT is turned off, another IO port (the second IO port) of the processor needs to be connected to the ON-OFF IO pin. When the high level at the ON-OFF IO pin makes the high level at the ILMDIS pin greater than Vref (the second reference voltage), the VIN to VOUT path is turned off, and the circuit in the existing solution enters the low-power mode. If a single IO port is used alone in the existing solution, for example, the ADC IO (the first IO port) of the processor connected to the ILMDIS pin (i.e., the target pin 5) introduces a high level greater than Vref (the second reference voltage) to turn off the power path of the constant current regulation mirror unit. Since the ON-OFF IO pin is fixedly grounded at this time, there will inevitably be a leakage current on the external current sensing resistor 33, and the leakage current is Vref / Rsense.

[0054] It can be seen that Figure 1 The solution shown requires two IO ports of the processor to achieve current sensing and low-power path on / off control.

[0055] In view of this, the present invention proposes a new power management circuit, which can achieve the above effects with only one IO port.

[0056] Regarding the solution of the present invention, the specific description is as follows:

[0057] Please refer to Figure 2 and Figure 3 , the power management circuit provided by the present invention includes: a constant current regulation mirror unit 1, a single-wire communication control unit 2, a current sensing resistor unit 3, an operational amplifier unit 4, and a target pin 5;

[0058] The first end of the current detection resistor unit 3 is grounded; the second end of the current detection resistor unit 3 is used to connect to the target pin 5; and the target pin 5 is also connected to the first input end of the single-wire communication control unit 2, the first end of the constant current regulation mirror unit 1, and the inverting input end of the operational amplifier unit 4; the first output end of the single-wire communication control unit 2 is connected to the non-inverting input end of the operational amplifier unit 4, and the output end of the operational amplifier unit 4 is connected to the second end of the constant current regulation mirror unit 1; the second output end of the single-wire communication control unit 2 is connected to the third end of the constant current regulation mirror unit 1; the target pin 5 is used to connect to the IO port of the processor; the constant current regulation mirror unit 1 further includes a voltage input terminal VIN and a voltage output terminal VOUT, and the voltage output terminal VOUT is used to supply power to an external electronic device.

[0059] The single-wire communication control unit 2 is a circuit unit characterized by realizing communication with an external circuit through external interaction and realizing the internal control of the circuit of the present invention.

[0060] The constant current regulation mirror unit 1 is a circuit unit characterized by an inductive resistor based on a mirror circuit architecture. By taking different resistance values, the maximum current flowing through the power supply path can be adjusted. When the current value exceeds this value, the power supply path is not turned off but the current is maintained without increasing; the constant current regulation mirror unit 1 can adopt existing implementation methods, and specifically, it can be implemented by various current mirrors. One implementation form, for example, can be the implementation method in the patent application with the application number "CN202111027616.4" and the title "Power Management Circuit and Electronic Device". Therefore, the present invention will not elaborate on this here.

[0061] Wherein, the operational amplifier unit 4 is used for: after the second end of the current detection resistor unit 3 is connected to the target pin 5 and the voltage output terminal VOUT forms a loop with an external electronic device, controlling the path between the voltage input terminal VIN and the voltage output terminal VOUT of the constant current regulation mirror unit 1 to conduct, and maintaining the current output from the voltage output terminal VOUT at the constant current point through negative feedback; and after the path conducts, based on the characteristics of the constant current regulation mirror unit 1 itself, the current output from the voltage output terminal VOUT is proportional to the current flowing through the current detection resistor unit 3. Specifically, the operational amplifier unit 4 includes an operational amplifier.

[0062] Therefore, in order to detect the current output from the voltage output terminal VOUT, it is only necessary to measure the voltage magnitude on the target pin 5, and then the current magnitude flowing through the current detection resistor unit 3 can be calculated; based on the current magnitude flowing through the current detection resistor unit 3, the current magnitude output from the voltage output terminal VOUT can be obtained. Therefore, the power management circuit provided by the present invention can easily implement the current detection function.

[0063] Among them, the single-wire communication control unit 2 is used to: control the turn-off of the constant-current regulation mirror unit 1 according to the first external control command input by the connected IO port.

[0064] The power management circuit provided by the present invention, through the single-wire communication control unit 2 and an IO port, enables the constant-current regulation mirror unit 1 to increase the function of digital communication control, and further can realize the turn-off of the constant-current regulation mirror unit 1 through an IO port; thus, the power management circuit provided by the present invention can realize the functions of current detection and turn-off only by using one IO port. Moreover, since the present invention receives an external control command through the single-wire communication control unit 2 to control the turn-off of the constant-current regulation mirror unit 1, at this time, the target pin 5 can be connected to a low level (such as grounded), so that there is no leakage current on the current detection resistor unit 3, and thus low-power turn-off can be realized.

[0065] Regarding the single-wire communication control unit 2 controlling the turn-off of the constant-current regulation mirror unit 1 according to the first external control command input by the connected IO port, it specifically may include:

[0066] Receiving the first external control command input by the IO port;

[0067] If the first external control command matches the preset control command in the single-wire communication control unit 2, then control the constant-current regulation mirror unit 1 to turn off.

[0068] The first external control command represents a first digital command composed of at least one logic bit; the preset control command represents a second digital command composed of at least one logic bit combination.

[0069] In an example, when the first external control command is one logic bit, the combined commands include: 0, 1. If the preset control command is 0, then when the first digital command input by the IO port is 0, the single-wire communication control unit 2 outputs a corresponding logic signal to the corresponding pin of the constant-current regulation mirror unit 1 (such as Figure 5 the Logic pin shown), to turn off the path of the constant-current regulation mirror unit 1. Of course, the preset control command can also be 1, then when the first digital command is 1, the single-wire communication control unit 2 outputs a corresponding logic signal to the corresponding pin of the constant-current regulation mirror unit 1 (such as Figure 5 the Logic pin shown), to turn off the path of the constant-current regulation mirror unit 1.

[0070] In one example, when the first external control command is composed of two logic bits, the combined commands include: 00, 01, 10, 11. If the preset control command is 00, then when the first digital command input through the IO port is 00, the single-wire communication control unit 2 outputs a corresponding logic signal to the corresponding pin of the constant-current regulation mirror unit 1 (such as Figure 5 the Logic pin shown), to turn off the path of the constant-current regulation mirror unit 1.

[0071] In another example, when the first external control command is composed of four logic bits, the combined commands include: 0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110, 1111. If the preset control command (second digital command) is 0000, then when the first digital command input through the IO port is 0000, the single-wire communication control unit 2 outputs a corresponding logic signal to turn off the path of the constant-current regulation mirror unit 1.

[0072] Of course, the present invention is not limited thereto, and combinations of other numbers of logic bits greater than or equal to 1 are also within the protection scope of the present invention. And it should be realized that the above preset control command can be flexibly set according to actual situations.

[0073] Moreover, during the process that the single-wire communication control unit 2 turns off the constant-current regulation mirror unit 1 according to the first external control command, the target pin 5 can be kept in a low-level (such as grounded) state, thereby avoiding the leakage current generated on the current detection resistor unit 3 when the constant-current regulation mirror unit is in the off state, and realizing the low-power-off function.

[0074] In a preferred embodiment of the present invention, the single-wire communication control unit 2 is further configured to: configure the first reference voltage at the non-inverting input terminal of the operational amplifier unit 4 according to the second external control command input through the connected IO port, so as to adjust the constant-current point of the current output through the voltage output terminal VOUT of the constant-current regulation mirror unit 1.

[0075] Regarding the constant-current point, a brief description is as follows:

[0076] Based on the fact that the magnitude of the output current (denoted as Iout) at the voltage output terminal VOUT of the constant-current regulation mirror unit 1 is proportional to the magnitude of the current flowing through the current-sensing resistor unit 3 (denoted as Isense), and since the target pin 5 is connected to the inverting input terminal of the operational amplifier unit 4, the voltage across the current-sensing resistor unit 3 forms negative feedback on the output of the operational amplifier unit 4. The negative feedback effect causes the value of Isense not to exceed the target current value, thereby restricting the magnitude of Iout (restricted below the constant-current point). By restricting the current in the current-sensing resistor unit 3 below the target current value, the output current can be restricted below a current value proportional to the target current value, and this output current value proportional to the target current value can be regarded as the constant-current point.

[0077] In other words, the constant-current control therein can be understood as setting the maximum current flowing through the power supply path in combination with the current-sensing resistor unit 3. When the externally supplied current exceeds this maximum current value, the power supply path is not turned off but the current is maintained without increase (it can also be expressed as: the output current at the output terminal VOUT of the constant-current regulation mirror unit 1 does not increase). Furthermore, this maximum current value (or a current value higher than this maximum current value) can be regarded as the constant-current point.

[0078] Such as Figure 1 The existing technology in [reference] adjusts the constant-current point by adjusting the magnitude of the current-sensing resistor to adjust the magnitude of the current flowing through the current-sensing resistor, so as to adjust the constant-current point. The present invention can also achieve the adjustment of the constant-current point based on the above approach. However, this way of adjusting the constant-current point requires the current-sensing resistor to be necessarily set outside the chip to achieve the adjustment of the magnitude of the current-sensing resistor.

[0079] In the solution of the preferred embodiment of the present invention, the first reference voltage at the non-inverting input terminal of the operational amplifier unit 4 is configured by the second external control command received by the single-wire communication control unit 2. By adjusting the reference voltage, the voltage across the current-sensing resistor in the case of reaching the constant-current point is adjusted, so that the constant-current point can be adjusted while the current-sensing resistor remains unchanged.

[0080] In Figure 2 In the shown solution, through the single-wire communication control unit 2, the first reference voltage of the operational amplifier unit 4 can also be adjusted by a digital command, and further, the constant-current point of the power supply path can be changed at any time, making the power management circuit more flexible in application.

[0081] In a specific embodiment, configuring the first reference voltage at the non-inverting input terminal of the operational amplifier unit 4 according to the second external control command input by the connected IO port to adjust the constant-current point of the output current at the voltage output terminal of the constant-current regulation mirror unit 1 includes:

[0082] Receiving the second external control command input by the IO port;

[0083] If the second external control command matches a preset configuration command in the single-wire communication control unit 2, the constant current point of the output current flowing through the voltage output terminal VOUT of the constant current regulation mirror unit 1 is adjusted, and the preset configuration command is characterized by the first reference voltages of different values.

[0084] The second external control command is characterized by a third digital command composed of at least one logical bit.

[0085] The preset configuration command is characterized by a fourth digital command composed of at least one logical bit, and different fourth digital commands correspond to different values of the first reference voltage.

[0086] In an example, when the second external control command is composed of a single logical bit, the combined commands include: 0 and 1, assuming that they represent the first reference voltage values of 0.2V and 0.4V respectively. If the preset configuration command is 0 (i.e., 0.2V), then when the third digital command input through the IO port is 0, the single-wire communication control unit 2 outputs a corresponding logical signal to configure the first reference voltage value to 0.2V. Of course, the first reference voltage values represented by 0 and 1 can be swapped, or they can be other values.

[0087] In an example, when the second external control command is composed of two logical bits, the combined commands include: 00, 01, 10, 11, representing the first reference voltage values of 0.2V, 0.4V, 0.6V, and 0.8V respectively. If the preset configuration command is 00 (i.e., 0.2V), then when the third digital command input through the IO port is 00, the single-wire communication control unit 2 outputs a corresponding logical signal to configure the first reference voltage value to 0.2V.

[0088] In another example, when the second external control command is composed of four logical bits, the combined commands include: 0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110, 1111, representing the first reference voltage values of 0.1V, 0.15V, 0.2V, 0.25V, 0.3V, 0.35V, 0.4V, 0.45V, 0.5V, 0.55V, 0.6V, 0.65V, 0.7V, 0.75V, 0.8V, 0.85V respectively. If the preset configuration command (fourth digital command) is 0000 (i.e., 0.1V), then when the third digital command input through the IO port is 0000, the single-wire communication control unit 2 outputs a corresponding logical signal to configure the first reference voltage value to 0.1V.

[0089] It should be noted that the value of the first reference voltage represented by the above command is only an example, and it can also be reasonably corresponded to the represented voltage value according to the situation, and can also represent other voltage values. The present invention is not limited thereto.

[0090] Regarding the control commands, in a specific embodiment, the first external control command and the second external control command can be combined together. In one example, when the first external control command and the second external control command are composed of four logical bits, the change of the last logical bit among the four logical bits represents the change of the first external control command. For example, XXX0 is to turn off the path of the constant current regulation mirror unit 1, and XXX1 is to turn on the path of the constant current regulation mirror unit 1; the change of the first three logical bits among the four logical bits represents the change of the second external control command. For example, 000X represents that the value of the first reference voltage is 0.1V.

[0091] Specifically, the first external control command and the second external control command operate on different data addresses inside the chip.

[0092] Of course, the present invention is not limited thereto, and the combination forms of other numbers of logical bits greater than or equal to 1 are also within the protection scope of the present invention. And it should be realized that the above preset control commands can be flexibly set according to the actual situation.

[0093] Regarding the current detection resistor unit 3, one way can be referred to Figure 4 , the current detection resistor unit 3 can specifically be an external current detection resistor 33. The first end of the external current detection resistor 33 is grounded, and the second end of the external current detection resistor 33 is used to connect to the target pin 5. As mentioned above, in this case, the present invention can adjust the constant current point in two ways. One way is to adjust the size of the external current detection resistor 33; the other way is to configure the first reference voltage at the non-inverting input end of the operational amplifier unit 4 by receiving the second external control command from the IO port through the single-wire communication control unit 2 to adjust the constant current point. Of course, the present invention preferably adjusts the constant current point through the single-wire communication control unit 2.

[0094] Since the present invention adjusts the constant current point through the single-wire communication control unit 2, the current detection resistor can remain unchanged. Therefore, the present invention can select a common current detection resistor and integrate it inside the chip. Thus, as another implementation method, as Figure 4As shown, the current detection resistor unit 3 includes a built-in current detection resistor 31 and a switch unit 32. The first end of the built-in current detection resistor 31 is connected to the first end of the switch unit 32. The second end of the switch unit 32 is grounded. The control end of the switch unit 32 is connected to the third output end of the single-wire communication control unit 2. The second end of the built-in current detection resistor 31 is used to connect to the target pin 5.

[0095] Specifically, the resistance value of the built-in current detection resistor 31 is such that it can achieve the control of a common constant current point in the application scenario. That is, the built-in current detection resistor 31 is a current detection resistor with a moderate resistance value and can achieve the control of a common constant current point.

[0096] In one example, the switch unit 32 is a switch, which can be used by the single-wire communication control unit to conduct or disconnect the built-in current detection resistor 31.

[0097] In another example, the switch unit 32 is a control circuit, which can be used by the single-wire communication control unit to conduct or disconnect the built-in current detection resistor 31.

[0098] Of course, the present invention is not limited thereto, and other forms of the switch unit 32 are within the protection scope of the present invention.

[0099] Among them, external and internal are relative to inside and outside the chip. In a specific implementation, when the current detection resistor unit is an external current detection resistor, the constant current regulation mirror unit 1, the single-wire communication control unit 2, the built-in current detection resistor 31, the switch unit 32, the operational amplifier unit 4, and the target pin 5 are provided inside the chip, and the external current detection resistor 33 is provided outside the chip.

[0100] When the current detection resistor unit is a built-in current detection resistor, the constant current regulation mirror unit 1, the single-wire communication control unit 2, the built-in current detection resistor 31, the switch unit 32, the operational amplifier unit 4, and the built-in current detection resistor and the switch unit are all provided inside the chip. The present invention pre-configures a current detection resistor (i.e., the built-in current detection resistor 31) with a moderate size and capable of achieving the control of a common constant current point inside the chip. In this way, when the single-wire communication control unit 2 configures this current detection resistor (i.e., the built-in current detection resistor 31) to take effect, there is no need to externally connect a current detection resistor (i.e., the external current detection resistor 33), so as to save costs and circuit board area.

[0101] Among them, the built-in current detection resistor 31 is controlled by the switch unit 2, and the on / off of the switch unit 32 is controlled by the single-wire communication control unit 2. Specifically, the single-wire communication control unit 2 can turn on the switch unit 32, so that the built-in current detection resistor 31 is connected between the ground and the target pin. Therefore, the built-in current detection resistor 31 can be used as the current detection resistor. At this time, there is no need to externally connect a current detection resistor, which saves the use of external components and also reduces the soldering cost of the circuit and the area of the system circuit board occupied by the circuit. When the single-wire communication control unit 2 is missing or fails, the switch unit 32 is turned off. At this time, the resistance of the branch where the built-in current detection resistor 31 is located can be regarded as infinite. At this time, the corresponding function can still be achieved by externally connecting a current detection resistor. Furthermore, it can be realized that even in the absence of the single-wire communication control unit 2 or when the single-wire communication control unit 2 fails, it will not affect any suitable current detection resistor required by the external application. Therefore, the present invention can also achieve the corresponding functions of the prior art even in the absence of the single-wire communication control unit or when the single-wire communication control unit fails.

[0102] Please continue to refer to Figure 4 , as a preferred embodiment, the power management circuit further includes a trigger unit 6. The non-inverting input terminal of the trigger unit 6 is connected to the target pin 5, the inverting input terminal of the trigger unit 6 is connected for inputting a second reference voltage, and the output terminal of the trigger unit 6 is connected to the fourth terminal of the constant current regulation mirror unit 1;

[0103] The trigger unit 6 is configured to: when the voltage of the IO port connected to the target pin 5 is greater than the second reference voltage, form a turn-off voltage at the output terminal to turn off the path between the voltage input terminal VIN and the voltage output terminal VOUT of the constant current mirror regulation unit 1.

[0104] Specifically, the trigger unit 6 includes a comparator.

[0105] In a specific embodiment, please refer to Figure 3, taking the current detection resistor unit as an external current detection resistor as an example, when the first end of the external current detection resistor 33 is grounded, Isense*Rsense (i.e., the external current detection resistor 33) can obtain the voltage VI*R. When the load (i.e., the external current detection resistor 33) does not draw a large enough current Iout, at this time VI*R < Vsense, the power supply path from VIN to VOUT (i.e., the power supply path between the constant current mirror adjustment units 1) is fully conductive. When the current Iout drawn by the load (i.e., the external current detection resistor 33) is large enough, such that VI*R > Vsense, the constant current mirror adjustment unit adjusts Iout to be maintained at n*Vsense / Rsense under the regulation of the output Current Control of the current operational amplifier AMP (i.e., the operational amplifier unit 4), that is, the constant current regulation control of Iout is achieved. In this circuit, the reference voltage of the voltage comparator CMP (i.e., the operational amplifier unit 4) is Vref (i.e., the second reference voltage). When VI*R > Vref, the output DISABLE of the comparator CMP (i.e., the trigger unit 6) enables the disabling of the constant current mirror adjustment unit and shuts off the power supply path from VIN to VOUT.

[0106] Of course, it should be realized that in the case where the single-wire communication control unit 2 is provided in the present invention, the trigger unit 6 may not be provided. The advantage of providing the trigger unit 6 in the preferred embodiment of the present invention is that it can achieve the shutdown of the power supply path even in the case where there is no single-wire communication control unit 2 or the single-wire communication control unit 2 malfunctions, so that the corresponding functions of the prior art can still be achieved in this case. And, in other embodiments, the Logic signal output by the single-wire communication control unit can not only shut off the power supply path and perform constant current point adjustment, but also control circuits such as CMP (i.e., the trigger unit 6) and AMP (i.e., the operational amplifier unit 4) to be in a low power consumption mode.

[0107] In addition, the following will be combined with Figure 3 , and then emphasize several important improvements in the specific solution of the present invention:

[0108] 1. By adopting a single-wire communication control unit, the external processor only needs to connect an IO port with ADC function to the ILMDIS pin (i.e., the target pin) of the circuit of the present invention to simultaneously achieve the current detection and shutdown functions;

[0109] In addition, the single-wire communication control unit added in the present invention can turn off the power path from VIN to VOUT and put the entire constant-current regulation mirror unit into a low-power mode by receiving digital commands from an external processor and then outputting Logic control commands. For example, it can make the ILMDIS pin (i.e., the target pin 5) at a logic ground level. That is, although the level at the ILMDIS pin (i.e., the target pin 5) is zero and less than Vref (i.e., the second reference voltage) at this time, it achieves the same effect as when the level at the ILMDIS pin (i.e., the target pin 5) is greater than Vref (i.e., the second reference voltage). Furthermore, it ensures that only one IO is connected to the ILMDIS pin (i.e., the target pin 5) to both turn off the VIN-to-VOUT channel and maintain the low power consumption of the constant-current regulation mirror unit.

[0110] Specifically, the ILMDIS pin (i.e., the target pin 5) can also receive digital commands (the second control command) and then configure the Vsense (i.e., the first reference voltage) voltage. Furthermore, the constant-current point of the output current from VIN to VOUT can be adjusted through the single-wire communication control unit 2 because the constant-current point is: N * Vsense / Rsense. Adjusting Vsense (i.e., the first reference voltage) can also adjust the constant-current of the VIN-to-VOUT channel.

[0111] 2. Adjust the constant-current point by using a built-in current-sensing resistor; the power management circuit of the present invention internally incorporates a conventional current-sensing resistor Rinsns (i.e., the built-in current-sensing resistor 31). In the scenario where the single-wire communication control unit 2 is supported, the switch unit 32 can be turned on through the single-wire communication control unit 2, enabling the internal Rinsns (i.e., the built-in current-sensing resistor 31) to be used as the current-sensing resistor to achieve the function originally requiring an external current-sensing resistor (i.e., the external current-sensing resistor 33). This saves the use of external components and reduces the soldering cost of the circuit and the area of the system circuit board occupied by the circuit.

[0112] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power management circuit, characterized in that, Including: A constant current regulation mirror unit, a single-wire communication control unit, a current detection resistor unit, an operational amplifier unit, and a target pin; The first end of the current detection resistor unit is grounded; the second end of the current detection resistor unit is used to connect to the target pin; and the target pin is also connected to the first input end of the single-wire communication control unit, the first end of the constant current regulation mirror unit, and the inverting input end of the operational amplifier unit; the first output end of the single-wire communication control unit is connected to the non-inverting input end of the operational amplifier unit, the output end of the operational amplifier unit is connected to the second end of the constant current regulation mirror unit; the second output end of the single-wire communication control unit is connected to the third end of the constant current regulation mirror unit; the target pin is used to connect to the IO port of the processor; the constant current regulation mirror unit further includes a voltage input end and a voltage output end, and the voltage output end is used to supply power to an external electronic device; Wherein, the operational amplifier unit is used for: after the second end of the current detection resistor unit is connected to the target pin and a loop is formed between the voltage output end and the external electronic device, controlling the path between the voltage input end and the voltage output end of the constant current regulation mirror unit to be turned on, and maintaining the current output from the voltage output end at a constant current point; and after the path is turned on, the current output from the voltage output end is proportional to the current flowing through the current detection resistor unit; The single-wire communication control unit is used for: Controlling the turn-off of the constant current regulation mirror unit according to a first external control command input by the connected IO port.

2. The power management circuit according to claim 1, wherein The controlling the turn-off of the constant current regulation mirror unit according to a first external control command input by the connected IO port includes: Receiving the first external control command input by the IO port; If the first external control command matches a preset control command in the single-wire communication control unit, controlling the constant current regulation mirror unit to turn off.

3. The power management circuit according to claim 2, characterized in that, The first external control command is represented by a first digital command composed of at least one logic bit; the preset control command is represented by a second digital command composed of at least one logic bit.

4. The power management circuit according to claim 1, wherein The single-wire communication control unit is further used for: Configuring a first reference voltage at the non-inverting input end of the operational amplifier unit according to a second external control command input by the connected IO port, so as to adjust the constant current point of the current output from the voltage output end of the constant current regulation mirror unit.

5. The power management circuit according to claim 4, wherein The configuring a first reference voltage at the non-inverting input end of the operational amplifier unit according to a second external control command input by the connected IO port, so as to adjust the constant current point of the current output from the voltage output end of the constant current regulation mirror unit includes: Receiving the second external control command input by the IO port; If the second external control command matches a preset configuration command in the single-wire communication control unit, adjusting the constant current point of the current output from the voltage output end of the constant current regulation mirror unit, and the preset configuration command is represented by different values of the first reference voltage.

6. The power management circuit according to claim 5, wherein The second external control command is characterized as a third digital command composed of at least one logical bit; the preset configuration command is characterized as a fourth digital command composed of at least one logical bit, and different fourth digital commands correspond to first reference voltages with different values.

7. The power management circuit according to claim 5, wherein The constant current point is N times the first reference voltage divided by the resistance value of the current detection resistor unit, where N is a positive number.

8. The power management circuit according to claim 1, characterized in that The current detection resistor unit includes an internal current detection resistor and a switch unit. The first end of the internal current detection resistor is connected to the first end of the switch unit. The second end of the switch unit is grounded, and the control end of the switch unit is connected to the third output end of the single-wire communication control unit; the second end of the internal current detection resistor is used to connect to the target pin.

9. The power management circuit according to claim 1, wherein The current detection resistor unit includes an external current detection resistor. The first end of the external current detection resistor is grounded, and the second end of the external current detection resistor is used to connect to the target pin.

10. The power management circuit according to any one of claims 1 to 9, characterized in that, It further includes a trigger unit. The non-inverting input terminal of the trigger unit is connected to the target pin. The inverting input terminal of the trigger unit is used to input a second reference voltage, and the output terminal of the trigger unit is connected to the fourth end of the constant current regulation mirror unit; The trigger unit is configured to: when the voltage of the IO port connected to the target pin is greater than the second reference voltage, form a turn-off voltage at the output terminal to turn off the path between the voltage input terminal and the voltage output terminal of the constant current regulation mirror unit.

11. The power management circuit according to claim 10, wherein, The operational amplifier unit includes an amplifier, and the trigger unit includes a comparator.

12. An electronic device, comprising the power management circuit according to any one of claims 1 to 11, and the processor.

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