AC-DC dual-purpose input low static power consumption circuit

Abstract

The utility model relates to the technical field of power supply circuits, and discloses an AC-DC dual-purpose input low static power consumption circuit with an automatic wake-up function and high reliability, which comprises an input step-down circuit (100), an output load circuit (200), a main control circuit (400), a load current detection circuit (500) and a sleep wake-up circuit (600), a control signal output by the main control circuit (400) is used for controlling the on / off state of the input step-down circuit (100); the main control circuit (400) is used for receiving a charging current signal, when the charging current signal is smaller than a charging preset value, the output control signal is a low level, and the low level switches off the input step-down circuit (100); the main control circuit (400) is used for receiving the wake-up signal and turning over the level state of the control signal according to the input wake-up signal so as to control the input step-down circuit (100) to be conducted.

Description

Technical Field

[0001] This utility model relates to the field of power supply circuit technology, and more specifically, to an AC-DC dual-use input low static power consumption circuit. Background Technology

[0002] Traditional AC / DC switching step-down converters use a switching power supply to step down 220V AC mains power to 18V DC. Users can plug the AC-to-DC converter into an AC power outlet (e.g., a wall socket) to charge the batteries in portable electronic devices.

[0003] However, the 18VDC switching between the internal battery's 25-40VDC may not be able to ensure that the switcher needs to re-operate the load; or it may not be able to achieve a static current loss of <15uA when there is no load. This results in prolonged battery drain, greatly shortens the lifespan of the internal battery, and is inconvenient to use, leading to a significant increase in cost and a short operating time. Utility Model Content

[0004] The technical problem to be solved by this utility model is to address the shortcomings of the existing technology, which cannot achieve a static current of <15uA under no-load conditions, resulting in long-term battery drain and significantly shortening the lifespan of the internal battery. This invention provides a low static power consumption circuit with automatic wake-up and high reliability for both AC and DC input.

[0005] The technical solution adopted by this utility model to solve its technical problem is: to construct an AC-DC dual-use input low static power consumption circuit, which has the following features:

[0006] The input buck circuit is configured at the front end of the low quiescent power circuit to receive DC voltage signals;

[0007] An output load circuit, whose input terminal is connected to the output terminal of the input step-down circuit, is used to receive the DC voltage signal and provide an electrical signal to the load.

[0008] The main control circuit has a preset charging value and outputs at least one control signal.

[0009] A signal output terminal of the main control circuit is connected to a signal input terminal of the input step-down circuit, and the control signal is used to control the on / off state of the input step-down circuit;

[0010] A load current detection circuit, the input of which is connected to one output of the output load circuit, is used to detect the charging current signal of the load.

[0011] One signal input terminal of the main control circuit is coupled to the output terminal of the load current detection circuit, and is used to receive the charging current signal.

[0012] When the charging current signal is less than the preset charging value, the output control signal is low, and the low level is used to turn off the input buck circuit.

[0013] The sleep-wake circuit has one input terminal connected to the other output terminal of the output load circuit. It is used to acquire an access signal generated when the load is connected to the output load circuit. This access signal triggers the sleep-wake circuit to output a wake-up signal.

[0014] The signal output terminal of the sleep-wake circuit is connected to a signal input terminal of the main control circuit for receiving the wake-up signal.

[0015] The main control circuit flips the level of the control signal according to the input wake-up signal to control the input buck circuit to turn on.

[0016] In some implementations, an AC input detection circuit is also included.

[0017] One input terminal of the AC input detection circuit is connected to the mains output terminal to receive AC signals.

[0018] One output terminal of the AC input detection circuit is connected to one signal input terminal of the input step-down circuit.

[0019] The output terminal of the AC input detection circuit is connected to one input terminal of the output load circuit, providing an electrical signal to the output load circuit.

[0020] When the main control circuit detects an AC current signal input, the output control signal is low to shut down the input step-down circuit.

[0021] In some implementations, an MCU power supply circuit is also included.

[0022] The first input terminal of the MCU power supply circuit is connected to the output terminal of the input step-down circuit to receive the first voltage signal.

[0023] The second input terminal of the MCU power supply circuit is connected to the output terminal of the AC input detection circuit to receive the second voltage signal.

[0024] The output terminal of the MCU power supply circuit is connected to the power input terminal of the main control circuit.

[0025] When the second voltage signal is greater than the first voltage signal, the AC input detection circuit provides a driving voltage to the main control circuit, and the input buck circuit is turned off.

[0026] In some embodiments, the MCU power supply circuit includes at least a twenty-sixth diode and a twenty-seventh diode.

[0027] The anode of the twenty-sixth diode is connected to the output terminal of the AC input detection circuit to receive the first voltage signal.

[0028] The anode of the 27th diode is connected to the output terminal of the input step-down circuit to receive the second voltage signal.

[0029] The cathodes of the 26th diode and the 27th diode are respectively connected to the power input terminal of the main control circuit.

[0030] In some embodiments, the input buck circuit includes at least a first MOSFET, a second MOSFET, and a buck converter.

[0031] The source of the first MOSFET is connected to the DC power input side to receive the DC voltage signal.

[0032] The drain of the first MOSFET is connected to the power input terminal of the buck converter.

[0033] The drain of the second MOSFET is connected to the gate of the first MOSFET through an eighth resistor.

[0034] The gate of the second MOSFET is connected to a signal output terminal of the main control circuit through the eleventh resistor and the twenty-second diode.

[0035] The enable terminal of the buck converter is connected to another signal output terminal of the main control circuit.

[0036] The output terminal of the buck converter is connected to the input terminal of the output load circuit.

[0037] The source of the second MOSFET is connected to the common terminal.

[0038] In some embodiments, the main control circuit includes at least a main controller.

[0039] One signal input terminal of the main controller is connected to one output terminal of the input step-down circuit.

[0040] The current signal feedback terminal of the main controller is connected to the output terminal of the load current detection circuit.

[0041] One signal output terminal of the main controller is connected to the gate of the second MOS transistor.

[0042] The other signal output terminal of the main controller is connected to the enable terminal of the buck converter.

[0043] In some implementations, a reference voltage regulator circuit is also included.

[0044] The first terminal of the reference voltage regulator circuit is connected to the enable terminal of the main control circuit.

[0045] The second terminal of the reference voltage regulator circuit is connected to the reference terminal of the main control circuit.

[0046] In some implementations, a momentary discharge circuit is also included.

[0047] The power input terminal of the instantaneous discharge circuit is connected to the output terminal of the AC input detection circuit.

[0048] One end of the instantaneous discharge circuit is connected to the release terminal of the main control circuit.

[0049] The AC-DC dual-use low quiescent power consumption input circuit of this invention includes an input step-down circuit, an output load circuit, a main control circuit, a load current detection circuit, and a sleep / wake-up circuit. The main control circuit outputs a control signal to control the on / off state of the input step-down circuit. The main control circuit receives a charging current signal; when the charging current signal is less than a preset charging value, the output control signal is low, shutting off the input step-down circuit. The main control circuit receives a wake-up signal and, based on the input wake-up signal, toggles the level of the control signal to control the input step-down circuit to conduct. Compared to existing technologies, by detecting whether a load is applied at the output, the battery step-down circuit enters a deep sleep mode when there is no load, ensuring that the battery's quiescent current loss is less than 15uA. When a load is applied, the wake-up circuit is immediately triggered to supply power to the load, reducing quiescent current loss. This solves the problem of inconvenient operation and extends battery life. Attached Figure Description

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0051] Figure 1 This is a circuit diagram of an embodiment of the input step-down circuit provided by this utility model;

[0052] Figure 2 This is a circuit diagram of an embodiment of the output load circuit and load current detection circuit provided by this utility model;

[0053] Figure 3 This is a circuit schematic diagram of an embodiment of the AC input detection circuit provided by this utility model;

[0054] Figure 4 This is a circuit diagram of an embodiment of the main control circuit and sleep / wake-up circuit provided by this utility model;

[0055] Figure 5 This is a circuit schematic diagram of an embodiment of the MCU power supply circuit provided by this utility model;

[0056] Figure 6 This is a circuit diagram of an embodiment of the reference voltage regulator circuit and instantaneous discharge circuit provided by this utility model. Detailed Implementation

[0057] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0058] like Figures 1-6 As shown, in the first embodiment of the AC-DC dual-use input low quiescent power circuit of this utility model, the AC-DC dual-use input low quiescent power circuit includes an input buck circuit 100, an output load circuit 200, an AC input detection circuit 300, a main control circuit 400, a load current detection circuit 500, a sleep wake-up circuit 600, an MCU power supply circuit 700, a reference voltage regulator circuit 800, and an instantaneous discharge circuit 900.

[0059] The input step-down circuit 100 is used to receive the voltage signal (such as 40VDC) from the pre-amplifier circuit or power supply input, and to filter and regulate the voltage signal to output a voltage of approximately 18VDC to the output load circuit 200.

[0060] The output load circuit 200 is used to receive the voltage signal input from the input step-down circuit 100 in order to drive the load to work;

[0061] The AC input detection circuit 300 is used to receive the voltage signal input from the mains side (~220V), then regulate and limit the input AC voltage signal, and output a voltage of about 20VDC to the output load circuit 200.

[0062] The main control circuit 400 is the core of the circuit. It has the functions of calculation, signal reception, comparison processing and control signal output. It is equipped with preset values ​​for charging current / voltage.

[0063] It outputs at least one control signal and one enable signal;

[0064] The load current detection circuit 500 is used to detect the current signal when the load is connected to the output load circuit 200, and amplify the current signal (e.g., amplify it by 50 times) and then feed it back to the main control circuit 400.

[0065] The sleep-wake circuit 600 is used to wake up the main control circuit 400, so as to flip the level of the output control signal, that is, from high level to low level, turn off the output of the input buck circuit 100, and then trigger the AC input detection circuit 300 to output a power signal to the output load circuit 200.

[0066] The MCU power supply circuit 700 is used to receive the power signal input from the input step-down circuit 100 or the AC input detection circuit 300, and to step down the power signal to output a 5V voltage signal for use by the main control circuit 400.

[0067] The instantaneous discharge circuit 900 is used to release the voltage signal of the peripheral circuit of the main control circuit 400 to avoid damage to electronic components due to voltage accumulation.

[0068] Specifically, the input step-down circuit 100 is configured at the front end of the low quiescent power circuit to receive a DC voltage signal (such as 40VDC), step down the DC voltage signal, and then output it to the output load circuit 200.

[0069] The input terminal of the output load circuit 200 is connected to the output terminal of the input step-down circuit 100 to receive DC voltage signals and provide electrical signals to the load (not shown).

[0070] Furthermore, the main control circuit 400 is provided with at least a charging preset value and at least one output control signal, wherein,

[0071] A signal output terminal of the main control circuit 400 is connected to a signal input terminal of the input step-down circuit 100, and the output control signal (high level / low level) is used to control the on / off state of the input step-down circuit 100;

[0072] When the input control signal is high, the input step-down circuit 100 is turned on.

[0073] When the input control signal is low, the input buck circuit 100 is turned off.

[0074] Furthermore, the input terminal of the load current detection circuit 500 is connected to one output terminal of the output load circuit 200, which is used to detect the charging current signal when the load is connected to the output load circuit 200, amplify the charging current signal, and then output it to the main control circuit 400.

[0075] One signal input terminal of the main control circuit 400 is coupled to the output terminal of the load current detection circuit 500 to receive the amplified charging current signal.

[0076] When the charging current signal is less than the preset charging value, the output control signal is low level, and the low level is used to turn off the input step-down circuit 100.

[0077] Furthermore, one input terminal of the sleep-wake circuit 600 is connected to the other output terminal of the output load circuit 200, used to acquire the access signal generated when the load is connected to the output load circuit 200. The access signal triggers the sleep-wake circuit 600 to output a wake-up signal.

[0078] The signal output terminal of the sleep-wake circuit 600 is connected to a signal input terminal of the main control circuit 400 to receive a wake-up signal.

[0079] The main control circuit 400 flips the level of the control signal according to the input wake-up signal, that is, flips from low level to high level, so as to control the input step-down circuit 100 to conduct and output a voltage signal to the output load circuit 200.

[0080] Using this technical solution, the battery step-down circuit enters a deep sleep mode when there is no load, so that the static current loss of the battery is less than 15uA. When a load is added, the wake-up circuit is immediately triggered to supply power to the load, reducing the static current loss. This not only solves the problem of inconvenient operation for users, but also extends the battery running time.

[0081] In some implementations, such as Figure 3 As shown, the circuit also includes an AC input detection circuit 300, wherein one input terminal of the AC input detection circuit 300 is connected to the mains output terminal for receiving AC signals and performing voltage regulation and rectification on the AC signals.

[0082] An output terminal of the AC input detection circuit 300 is connected to a signal input terminal of the input step-down circuit 100, and is used to acquire the electrical signal of the AC input detection circuit 300 at the moment it is connected to the mains power.

[0083] The output terminal of the AC input detection circuit 300 is connected to one input terminal of the output load circuit 200, providing an electrical signal to the output load circuit 200.

[0084] When the main control circuit 400 detects an AC current signal input, the output control signal is low to shut down the input step-down circuit 100, and the AC input detection circuit 300 outputs a power signal instead.

[0085] The AC input detection circuit includes at least a fifteenth MOSFET and a twelfth diode D15.

[0086] The gate of the fifteenth MOSFET is connected to the AC power input terminal through the twenty-fifth resistor R25 and the twentieth diode D20. The drain of the fifteenth MOSFET is connected to one end of the sleep / wake-up circuit 600. The drain of the fifteenth MOSFET is connected to a signal input terminal of the input buck circuit 100 through the twenty-first diode D21.

[0087] The anode of the twelfth diode D15 is connected to the AC power input terminal, and the cathode of the twelfth diode D15 is connected to an input terminal of the output load circuit 200, providing an electrical signal to the output load circuit 200.

[0088] In some implementations, such as Figure 5 As shown, to ensure the reliability of switching between DC and AC signals, an MCU power supply circuit 700 can be set in the circuit. The first input terminal of the MCU power supply circuit 700 is connected to the output terminal of the input step-down circuit 100 to receive the first voltage signal.

[0089] The second input terminal of the MCU power supply circuit 700 is connected to the output terminal of the AC input detection circuit 300 to receive the second voltage signal.

[0090] The output of the MCU power supply circuit 700 is connected to the power input of the main control circuit 400.

[0091] When the second voltage signal is greater than the first voltage signal, the AC input detection circuit 300 provides driving voltage to the main control circuit 400, and the input step-down circuit 100 is turned off.

[0092] In some implementations, such as Figure 5 As shown, to ensure the reliability of switching between DC and AC signals, a first linear regulator U6, a second linear regulator U2, a twenty-sixth diode D26, and a twenty-seventh diode D27 can be installed in the MCU power supply circuit 700.

[0093] The anode of the thirtieth diode D30 is connected to one output terminal (corresponding to an LDO) of the input step-down circuit 100 to receive the second voltage signal (DC signal).

[0094] The cathode of the thirtieth diode D30 is connected to the input terminal of the first linear regulator U6. The output terminal of the first linear regulator U6 is connected to the anode of the twenty-seventh diode D27. The cathode of the twenty-seventh diode D27 is connected to the input terminal of the second linear regulator U2. The output terminal of the second linear regulator U2 is connected to the power input terminal of the main control circuit 400.

[0095] Furthermore, the anode of the twenty-sixth diode D26 is connected to the output terminal (corresponding to ACO) of the AC input detection circuit 300 to receive the first voltage signal (AC signal).

[0096] The cathode of the twenty-sixth diode D26 is connected to the input terminal of the second linear regulator U2 through the fifty-eighth resistor R58, and the output terminal of the second linear regulator U2 is connected to the power input terminal of the main control circuit 400.

[0097] When the anode voltage of the twenty-sixth diode D26 is higher than the anode voltage of the twenty-seventh diode D27, the twenty-seventh diode D27 is in the off state. At this time, the AC input detection circuit 300 provides the driving voltage to the main control circuit 400, and the input step-down circuit 100 is turned off.

[0098] In some implementations, such as Figure 1 As shown, in order to ensure the reliability of the output voltage signal, the input step-down circuit 100 may include at least a first MOSFET Q1, a second MOSFET Q2, and a step-down converter U1. The first MOSFET Q1 is selected as a P-channel MOSFET, the second MOSFET Q2 is selected as an N-channel MOSFET, and the step-down converter U1 has the function of stepping down the voltage.

[0099] Specifically, the source of the first MOSFET Q1 is connected to the DC power input side (corresponding to +40VIN) to receive the DC voltage signal and filter the DC voltage signal.

[0100] The drain of the first MOSFET Q1 is connected to the power input terminal (pin 2) of the buck converter U1. The input DC voltage signal triggers the buck converter U1.

[0101] The drain of the second MOSFET Q2 is connected to the gate of the first MOSFET Q1 through the eighth resistor R8.

[0102] The gate of the second MOSFET Q2 is connected to one end of the eleventh resistor R11.

[0103] The other end of the eleventh resistor R11 is connected to the cathode of the twenty-second diode D22.

[0104] The anode of the twenty-second diode D22 is connected to a signal output terminal of the main control circuit 400. The control signal output by the main control circuit 400 is input to the gate of the second MOSFET Q2 via the twenty-second diode D22 and the eleventh resistor R11.

[0105] When the input control signal is high, the second MOSFET Q2 is turned on, and the gate potential of the first MOSFET Q1 is pulled low and turned on.

[0106] The enable terminal (corresponding to pin 3) of the buck converter U1 is connected to another signal output terminal of the main control circuit 400 to receive the enable signal;

[0107] The output terminal (corresponding to pin 8) of the buck converter U1 is connected to the input terminal of the output load circuit 200.

[0108] The source of the second MOSFET Q2 is connected to the common terminal.

[0109] In some implementations, such as Figure 4 As shown, in order to ensure the reliability of AC / DC signal switching, a main controller U5 can be set in the main control circuit 400, which has functions such as signal output, signal processing, and calculation.

[0110] Specifically, one signal input terminal (corresponding to pin 20) of the main controller U5 is connected to one output terminal (corresponding to the AD-BAT terminal) of the input step-down circuit 100.

[0111] The current signal feedback terminal (corresponding to pin 18) of the main controller U5 is connected to the output terminal (corresponding to the ADC-IN terminal) of the load current detection circuit 500 to receive the charging current signal;

[0112] One signal output terminal (corresponding to pin 3) of the main controller U5 is connected to the gate of the second MOSFET Q2 through the twenty-second diode D22 and the eleventh resistor R11, and is used to output control signals;

[0113] The other signal output terminal of the main controller U5 (corresponding to pin 2) is connected to the enable terminal of the buck converter U1 (corresponding to pin 3).

[0114] In some implementations, such as Figure 6 As shown, the circuit also includes a reference voltage regulator circuit 800, wherein the first terminal of the reference voltage regulator circuit 800 (corresponding to the EN-REF terminal) is connected to the enable terminal (corresponding to pin 2) of the main controller U5 (belonging to the main control circuit 400).

[0115] The second terminal (corresponding to the VREF terminal) of the reference voltage regulator circuit 800 is connected to the reference terminal (corresponding to pin 1) of the main controller U5 (belonging to the main control circuit 400) to feed back the reference signal to the main control circuit 400.

[0116] In some implementations, such as Figure 6 As shown, the circuit also includes an instantaneous discharge circuit 900, wherein,

[0117] The power input terminal of the instantaneous discharge circuit 900 is connected to the output terminal (corresponding to the 20VDC terminal) of the AC input detection circuit 300.

[0118] One end of the instantaneous discharge circuit 900 is connected to the release terminal (pin 16) of the main controller U5 (which belongs to the main control circuit 400).

[0119] The instantaneous discharge circuit 900 includes at least the fourteenth MOSFET Q14.

[0120] The gate of the fourteenth MOSFET Q14 is connected to the release terminal (pin 16) of the main controller U5 through the sixtieth resistor R60, and the drain of the fourteenth MOSFET Q14 is connected to the output terminal (20VDC terminal) of the AC input detection circuit 300 through resistors R55, R56 and R69 connected in parallel.

[0121] When the release signal output by the main controller U5 is high, the fourteenth MOSFET Q14 is turned on, thereby discharging the energy storage components around the main controller U5.

[0122] Its working principle is as follows:

[0123] When the 25-40VDC voltage signal at the battery input terminal is input through the input step-down circuit 100, the main controller U5 directly outputs a high level to the gate of the second MOSFET Q2, thereby turning on the first MOSFET Q1. The voltage is used to form the battery voltage through the twenty-third resistor R23 and the twenty-ninth resistor R29. When the battery voltage is not lower than 25V, the second MOSFET Q2 continues to work.

[0124] When the battery voltage is below 25V, the main controller U5 flips the control signal level from high to low, causing the second MOSFET Q2 to stop working and the first MOSFET Q1 to be turned off.

[0125] When the first MOSFET Q1 is turned on, the input voltage signal causes the buck converter U1 to operate, thereby achieving a buck output. The bucked voltage is then output to the load via the output load circuit 200. When the load is connected to the output load circuit 200, it detects the charging current signal through the seventeenth resistor (R17A, R17B) and the twenty-eighth resistor R28. The detected charging current signal is input to the non-inverting input (corresponding to pin 3) of the operational amplifier U3, and the inverting input (corresponding to pin 4) is connected to the output terminal (corresponding to pin 4) through the thirty-fifth resistor R35.

[0126] The charging current signal is output from the output terminal (pin 1) of operational amplifier U3 to pin 23 of main controller U5. When the load current is less than 12mA, the control signal output from pin 3 of main controller U5 is low, turning off the second MOSFET Q2 and cutting off the first MOSFET Q1. After 15 seconds, the circuit enters sleep mode. At this time, the output load circuit 200 should be in a no-load state. When the output load circuit 200 is connected to a load and the load operation button is activated, the voltage signal (20VDC) passes through the seventeenth diode D17 to the drain of the sixteenth MOSFET Q16. The gate of the sixteenth MOSFET Q16 is connected to the drain of the fifteenth MOSFET Q15 through the seventieth resistor R70.

[0127] Among them, the fifty-fourth resistor R54, the thirty-third capacitor C33, and the collector of the thirteenth transistor Q13 are connected to pin 13 of the main controller U5. The connected load momentarily pulls down the potential of the base of the thirteenth transistor Q13, causing the collector of the thirteenth transistor Q13 to change from high to low signal, waking up the main controller U5 to give the second MOSFET Q2 a high level to control the first MOSFET Q1 to work. While the first MOSFET Q1 is working, it will provide power to the MCU power supply circuit 700. The first linear regulator U6 steps down the input 40V voltage to 12V. The 12V voltage is then stepped down to 5V by the second linear regulator U2 and then provides the working voltage to the main controller U5.

[0128] When AC~220V voltage is input to AC input detection circuit 300, it is output to output load circuit 200 through diode D15, and then power is supplied to the load. At this time, the level of pin 13 of the main controller U5 is pulled to high level through resistor R59, and AC signal input is detected. At the same time, capacitor EC4 is charged through resistor R21, diode D24, and diode D25. The level of pin P13 of the main controller U5 is pulled low through MOSFET Q15. The control signal (low level) output by the main controller U5 is sent to the gate of the second MOSFET Q2 through diode D22, turning off the second MOSFET Q2 and the first MOSFET Q1.

[0129] Meanwhile, because the anode voltage of the 26th diode D26 is higher than the cathode voltage, meaning the cathode voltage of the 27th diode D27 is higher than the anode voltage, the 27th diode D27 is cut off. At this time, the main controller U5 is powered by AC, and the 25-40VDC battery terminal is no longer powered. The low quiescent current of the 25-40VDC battery at this time is 5.4uA.

[0130] The first MOSFET Q1 is in the off state, and the input to the step-down circuit 100 is no longer input. In this way, the battery is in a low-loss off state and its life will not be damaged by switching. After 3 seconds, the main controller U5 is in sleep state. Conversely, if the AC input is removed, it will discharge immediately because EC4 was already charged at the beginning.

[0131] Because the voltage passes through the forty-eighth resistor R48, then through the thirty-fourth diode D34, and the seventieth resistor R70, it causes the sixteenth MOSFET Q16 to change from the cutoff state to the on state, pulling down the base voltage of the thirteenth transistor Q13, causing the thirteenth transistor Q13 to change from cutoff to on, and the collector of the thirteenth transistor Q13 to change from low level to high level, thus waking up the main controller U5.

[0132] The power supply of the main control circuit 400 has been changed from the original AC power supply to a 25-40VDC circuit power supply. The main controller U5 is always in working state, thus realizing the priority of AC power supply and not shutting down the load working state due to the switching between the two.

[0133] The above technical solutions address users' concerns about battery damage caused by both AC and battery input. By prioritizing AC input and minimizing quiescent current loss, these solutions not only reduce operational inconvenience but also extend battery life.

[0134] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A low quiescent power consumption circuit for AC-DC dual-use input, characterized in that, have: The input buck circuit is configured at the front end of the low quiescent power circuit to receive DC voltage signals; An output load circuit, whose input terminal is connected to the output terminal of the input step-down circuit, is used to receive the DC voltage signal and provide an electrical signal to the load. The main control circuit has a preset charging value and outputs at least one control signal. A signal output terminal of the main control circuit is connected to a signal input terminal of the input step-down circuit, and the control signal is used to control the on / off state of the input step-down circuit; A load current detection circuit, the input of which is connected to one output of the output load circuit, is used to detect the charging current signal of the load. One signal input terminal of the main control circuit is coupled to the output terminal of the load current detection circuit, and is used to receive the charging current signal. When the charging current signal is less than the preset charging value, the output control signal is low, and the low level is used to turn off the input buck circuit. The sleep-wake circuit has one input terminal connected to the other output terminal of the output load circuit. It is used to acquire an access signal generated when the load is connected to the output load circuit. This access signal triggers the sleep-wake circuit to output a wake-up signal. The signal output terminal of the sleep-wake circuit is connected to a signal input terminal of the main control circuit for receiving the wake-up signal. The main control circuit flips the level of the control signal according to the input wake-up signal to control the input buck circuit to turn on.

2. The AC-DC dual-use input low quiescent power circuit according to claim 1, characterized in that, It also includes an AC input detection circuit. One input terminal of the AC input detection circuit is connected to the mains output terminal to receive AC signals. One output terminal of the AC input detection circuit is connected to one signal input terminal of the input step-down circuit. The output terminal of the AC input detection circuit is connected to one input terminal of the output load circuit, providing an electrical signal to the output load circuit. When the main control circuit detects an AC current signal input, the output control signal is low to shut down the input step-down circuit.

3. The AC-DC dual-use input low quiescent power circuit according to claim 2, characterized in that, It also includes the MCU power supply circuit. The first input terminal of the MCU power supply circuit is connected to the output terminal of the input step-down circuit to receive the first voltage signal. The second input terminal of the MCU power supply circuit is connected to the output terminal of the AC input detection circuit to receive the second voltage signal. The output terminal of the MCU power supply circuit is connected to the power input terminal of the main control circuit. When the second voltage signal is greater than the first voltage signal, the AC input detection circuit provides a driving voltage to the main control circuit, and the input buck circuit is turned off.

4. The AC-DC dual-use input low quiescent power circuit according to claim 3, characterized in that, The MCU power supply circuit includes at least a twenty-sixth diode and a twenty-seventh diode. The anode of the twenty-sixth diode is connected to the output terminal of the AC input detection circuit to receive the first voltage signal. The anode of the 27th diode is connected to the output terminal of the input step-down circuit to receive the second voltage signal. The cathodes of the 26th diode and the 27th diode are respectively connected to the power input terminal of the main control circuit.

5. The AC-DC dual-use input low quiescent power circuit according to claim 3, characterized in that, The input buck circuit includes at least a first MOSFET, a second MOSFET, and a buck converter. The source of the first MOSFET is connected to the DC power input side to receive the DC voltage signal. The drain of the first MOSFET is connected to the power input terminal of the buck converter. The drain of the second MOSFET is connected to the gate of the first MOSFET through an eighth resistor. The gate of the second MOS transistor is connected to a signal output terminal of the main control circuit through the eleventh resistor and the twenty-second diode. The enable terminal of the buck converter is connected to another signal output terminal of the main control circuit. The output terminal of the buck converter is connected to the input terminal of the output load circuit. The source of the second MOSFET is connected to the common terminal.

6. The AC-DC dual-use input low quiescent power circuit according to claim 5, characterized in that, The main control circuit includes at least a main controller. One signal input terminal of the main controller is connected to one output terminal of the input step-down circuit. The current signal feedback terminal of the main controller is connected to the output terminal of the load current detection circuit. One signal output terminal of the main controller is connected to the gate of the second MOS transistor. The other signal output terminal of the main controller is connected to the enable terminal of the buck converter.

7. The AC-DC dual-use input low quiescent power circuit according to claim 1, characterized in that, It also includes a reference voltage regulator circuit. The first terminal of the reference voltage regulator circuit is connected to the enable terminal of the main control circuit. The second terminal of the reference voltage regulator circuit is connected to the reference terminal of the main control circuit.

8. The AC-DC dual-use input low quiescent power circuit according to claim 2, characterized in that, It also includes a momentary discharge circuit. The power input terminal of the instantaneous discharge circuit is connected to the output terminal of the AC input detection circuit, and one end of the instantaneous discharge circuit is connected to the release terminal of the main control circuit.

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