Power supply starting circuit, power supply circuit and electronic equipment

Abstract

The utility model relates to a power startup circuit, a power circuit and an electronic device. The power startup circuit includes: a power controller, a charging unit, a charging input control unit and a charging input unit; the charging input control unit is connected to an external power input and the charging input unit and the charging unit, and is used to generate a driving level to drive the charging input unit to turn on or off; the charging input unit is connected to an external power input and the charging unit, and is used to charge the charging unit when turned on, and to turn off the charging of the charging unit when turned off; the charging unit is connected to a power controller, and is used to generate a charging voltage and supply power to the power controller through the charging voltage to start the power controller; the charging input control unit is also connected to the power controller, and is used to receive a first control level output by the power controller and generate a driving level or turn off the driving level. The implementation of the utility model can improve the startup speed of the power supply, while reducing circuit loss and improving power efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, and more specifically to a power start-up circuit, a power circuit and an electronic device. Background Art

[0002] The application of power supplies is becoming more and more common, so the design of power supplies is becoming more and more important, and improving the performance of power supplies is also particularly important.

[0003] Among the current solutions that use analog chips, i.e. power chips, as power control solutions, the most widely used power start-up solution is Figure 5 The scheme shown. R1 is the starting resistor, C2 is the starting support capacitor, and the starting support capacitor C2 is charged through the starting resistor R1. After the starting support capacitor C2 is charged to the starting voltage of the switching power supply chip, the power supply starts. During the startup process of the power chip, in order to reduce the startup time, the resistor R1 and the capacitor C2 need to be as small as possible. After the power chip is started, in order to reduce the power loss on the starting resistor R1, the starting resistor R1 needs to be as large as possible. In addition, during the startup process of the power chip, the starting support capacitor C2 is needed to provide energy, and the capacity of the capacitor C2 is required. Therefore, in the process of balancing the resistor R1 and the capacitor C2, there are inevitably problems of large resistance loss and long startup time. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a power supply starting circuit, a power supply circuit and an electronic device in view of the above-mentioned technical defects of the prior art.

[0005] The technical solution adopted by the utility model to solve the technical problem is: constructing a power startup circuit, including: a power controller, a charging unit, a charging input control unit and a charging input unit;

[0006] The charging input control unit is connected to an external power input as well as the charging input unit and the charging unit, and is used to generate a driving level to drive the charging input unit to be turned on or off;

[0007] The charging input unit is connected to the external power input and the charging unit, and is used to charge the charging unit when it is turned on, and to shut down the charging of the charging unit when it is turned off;

[0008] The charging unit is connected to the power controller and is used to generate a charging voltage and supply power to the power controller through the charging voltage so as to start the power controller;

[0009] The charging input control unit is also connected to the power controller, and is used to receive the first control level output by the power controller and generate the driving level or turn off the driving level.

[0010] Preferably, in the power startup circuit of the utility model, the charging input control unit includes a first resistor, a first control switch, a first diode, a second resistor and a voltage regulator;

[0011] The first end of the first resistor is connected to the external power input, the second end of the first resistor is connected to the first end of the first control switch and the anode of the first diode, the cathode of the first diode is connected to the charging input unit and the first end of the second resistor and the cathode of the Zener diode, the second end of the second resistor and the anode of the Zener diode are connected to the charging unit, the second end of the first control switch is connected to the negative electrode of the external power input, and the control end of the first control switch is connected to the first signal output end of the power controller.

[0012] Preferably, in the power startup circuit of the utility model, the first control switch includes a first MOS tube;

[0013] The source of the first MOS tube is connected to the negative electrode of the external power input, the gate of the first MOS tube is connected to the power controller, and the drain of the first MOS tube is connected to the second end of the first resistor and the anode of the first diode.

[0014] Preferably, in the power startup circuit of the utility model, the charging input unit includes a third resistor and a second control switch;

[0015] The first end of the third resistor is connected to the external power input, the second end of the third resistor is connected to the first end of the second control switch, the second end of the second control switch is connected to the charging unit, and the control end of the second control switch is connected to the charging input control unit for receiving the driving level.

[0016] Preferably, in the power startup circuit of the utility model, the second control switch includes a second MOS tube;

[0017] The drain of the second MOS tube is connected to the second end of the third resistor, the source of the second MOS tube is connected to the charging unit, and the gate of the second MOS tube is used to receive the driving level.

[0018] Preferably, in the power startup circuit of the utility model, the charging unit includes a charging capacitor;

[0019] The first end of the charging capacitor is connected to the power input end of the power controller, the charging input unit and the charging input control unit, and the second end of the charging capacitor is connected to the negative electrode of the external power input.

[0020] The utility model also constructs a power supply circuit, comprising: the power supply starting circuit as described above; and a power supply output unit;

[0021] The power output unit is connected to the power controller, and is used to receive the second control level output by the power controller and generate a first output voltage to power the power controller and to generate a second output voltage as power output.

[0022] Preferably, in the power supply circuit described in the utility model, the power output unit includes a second diode, a third control switch and a voltage output circuit;

[0023] The first input terminal of the voltage output circuit is connected to the external power input, the first terminal of the third control switch is connected to the second input terminal of the voltage output circuit, the second terminal of the third control switch is connected to the negative electrode of the external power input, and the control terminal of the third control switch is connected to the second signal output terminal of the power controller;

[0024] The anode of the second diode is connected to the first output terminal of the voltage output circuit, and the second output terminal of the voltage output circuit is connected to the negative electrode of the external power input.

[0025] Preferably, in the power supply circuit of the utility model, the voltage output circuit comprises a transformer; wherein the transformer comprises an input winding, a first output winding and a second output winding;

[0026] The first end of the input winding is connected to the external power input, and the second end of the input winding is connected to the first end of the third control switch;

[0027] A first end of the first output winding is connected to the anode of the second diode, and a second end of the first output winding is connected to the negative electrode of the external power input;

[0028] The second output winding is used to generate the second output voltage.

[0029] Preferably, in the power supply circuit of the present utility model, the third control switch comprises a third MOS tube;

[0030] The drain of the third MOS tube is connected to the second end of the input winding, the source of the third MOS tube is connected to the negative electrode of the external power input, and the gate of the third MOS tube is connected to the second signal output end of the power controller.

[0031] The utility model also constructs an electronic device, comprising the power supply circuit as described above.

[0032] A power startup circuit, a power circuit and an electronic device implementing the utility model have the following beneficial effects: the startup speed of the power supply can be increased, while circuit loss can be reduced, power efficiency can be improved, and power consumption during standby mode can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0034] Figure 1 It is a logic schematic diagram of an embodiment of a power supply starting circuit of the utility model;

[0035] Figure 2 This is a circuit schematic diagram of an embodiment of a power start-up circuit of the utility model;

[0036] Figure 3 It is a logic schematic diagram of an embodiment of a power supply circuit of the utility model;

[0037] Figure 4 This is a circuit schematic diagram of an embodiment of a power supply circuit of the utility model;

[0038] Figure 5 It is a circuit schematic diagram of an embodiment of the current power startup circuit. DETAILED DESCRIPTION

[0039] In order to have a clearer understanding of the technical features, purposes and effects of the present utility model, the specific implementation methods of the present utility model are now described in detail with reference to the accompanying drawings.

[0040] Figure 1 FIG. 1 shows an embodiment of a power supply startup circuit of the utility model. Figure 1 As shown, the power startup circuit of the utility model includes: a power controller 110, a charging unit 140, a charging input control unit 120 and a charging input unit 130; the charging input control unit 120 is connected to the external power input 200, the charging input unit 130 and the charging unit 140, and is used to generate a driving level to drive the charging input unit 130 to be turned on or off; the charging input unit 130 is connected to the external power input 200 and the charging unit 140, and is used to charge the charging unit 140 when it is turned on, and to turn off the charging of the charging unit 140 when it is turned off; the charging unit 140 is connected to the power controller 110, and is used to generate a charging voltage and supply power to the power controller 110 through the charging voltage to start the power controller 110; the charging input control unit 120 is also connected to the power controller 110, and is used to receive the first control level output by the power controller 110 and generate a driving level or turn off the driving level.

[0041] Specifically, in the power startup circuit, the power controller 110 is controlled to power on and start up. After the power controller 110 is started up, the power controller 110 can control the working process of the entire power supply. Therefore, the process of controlling the startup of the power controller 110 can be understood as the startup process of the corresponding power circuit. Among them, the first end of the charging input control unit 120 is connected to the external power input 200, the second end of the charging input control unit 120 is connected to the charging input unit 130, and the third end of the charging input control unit 120 is connected to the charging unit 140. The charging input control unit 120 is used to receive the external power input 200 and generate a driving level. When the charging input unit 130 receives the driving level, it is turned on or off according to the driving level. The charging unit 140 is connected to the charging input unit 130. When the charging input unit 130 is turned on, the charging unit 140 is charged through the input of the charging input unit 130. When the charging input unit 130 is turned off, the charging unit 140 stops charging. The charging unit 140 generates a charging voltage during the charging process, and the power controller 110 is connected to the charging unit 140 and powered on by the charging voltage of the charging unit 140. After the power controller 110 is started, the corresponding power circuit can also be understood to have completed the startup process. In addition, the charging input control circuit is also connected to the power controller 110. After the power controller 110 is powered on and started, the charging input control unit 120 can be controlled by the first control level output by the power controller 110 to generate a drive level or turn off the drive level. That is, the charging input unit 130 is finally turned on or off. In some scenarios, after the power controller 110 is started, the power supply circuit of the power controller 110 can be switched to maintain the power supply of the power controller 110 through other circuits. At this time, the charging input unit 130 can be turned off to reduce the power consumption on the charging input unit 130.

[0042] like Figure 2As shown, in one embodiment, the charging input control unit 120 includes a first resistor, a first control switch, a first diode, a second resistor and a voltage regulator; the first end of the first resistor is connected to the external power input 200, the second end of the first resistor is connected to the first end of the first control switch and the anode of the first diode, the cathode of the first diode is connected to the charging input unit 130, the first end of the second resistor and the cathode of the voltage regulator, the second end of the second resistor and the anode of the voltage regulator are connected to the charging unit 140, the second end of the first control switch is connected to the negative electrode of the external power input 200, and the control end of the first control switch is connected to the first signal output end of the power controller 110. Specifically, the first control switch is in the off state by default. When the first control switch is turned off, the external power input 200 forms a high voltage at the anode of the first diode through the first resistor. When the first diode is turned on, the external power input 200 generates a driving level at the cathode of the second diode after the voltage division of the first resistor and the second resistor. The voltage regulator is used to clamp the voltage division so that the value of the driving level can drive the charging input unit 130 to turn on. As shown in FIG. Figure 2 As shown, the first resistor may include a resistor R1, the second resistor may include a resistor R2, the first diode may include a diode D1, and the voltage regulator may include a voltage regulator D3. The resistor R2 is a large resistance.

[0043] Optionally, in the power startup circuit of the utility model, the first control switch includes a first MOS tube; the source of the first MOS tube is connected to the negative electrode of the external power input 200, the gate of the first MOS tube is connected to the power controller 110, and the drain of the first MOS tube is connected to the second end of the first resistor and the anode of the first diode. Specifically, the first control switch can be composed of a MOS tube. In a specific embodiment, the first MOS tube can include a MOS tube Q1, wherein the MOS tube Q1 can be an NMOS tube, and the default state is an off state. When the MOS tube Q1 is in the off state, the drain of the MOS tube Q1 forms a high level at the anode of the diode D1, and the diode D1 is turned on.

[0044] Optionally, in the power startup circuit of the present utility model, the charging input unit 130 includes a third resistor and a second control switch; the first end of the third resistor is connected to the external power input 200, the second end of the third resistor is connected to the first end of the second control switch, the second end of the second control switch is connected to the charging unit 140, and the control end of the second control switch is connected to the charging input control unit 120 for receiving the driving level. Specifically, in the charging input unit 130, the second control switch can be driven on or off by the driving level generated by the charging input control unit 120. When the second control switch is turned on, the external power input 200 charges the charging unit 140 through the third resistor and the second control switch. The third resistor may include a resistor R3, which is a small resistance resistor to reduce power consumption during charging.

[0045] Further, the second control switch includes a second MOS tube; the drain of the second MOS tube is connected to the second end of the third resistor, the source of the second MOS tube is connected to the charging unit 140, and the gate of the second MOS tube is used to receive the driving level. Specifically, the second control switch can be composed of a MOS tube. In a specific embodiment, the second MOS tube may include a MOS tube Q2. The gate of the MOS tube Q2 is connected to the cathode of the diode D1, the first end of the resistor R2, and the cathode of the voltage regulator tube D3, and receives the driving level generated by the voltage division of the resistor R1 and the resistor R2 to turn on. After the MOS tube Q2 is turned on, the external power input 200 is input to the charging unit 140 through the resistor R3 and the MOS tube Q2 to charge the charging unit 140.

[0046] Optionally, the charging unit 140 includes a charging capacitor; the first end of the charging capacitor is connected to the power input terminal of the power controller 110, the charging input unit 130 and the charging input control unit 120, and the second end of the charging capacitor is connected to the negative electrode of the external power input 200. Specifically, the charging unit 140 can be composed of a charging capacitor. In a specific embodiment, the charging capacitor may include a capacitor C1. The first end of the capacitor C1 is connected to the charging input unit 130 and the charging input control unit 120, and the second end of the capacitor C1 is connected to the negative electrode of the external power input 200. When the external power input 200 is charged, the first end of the capacitor C1 generates a charging voltage. When the charging voltage reaches a certain value, the power input terminal of the power controller 110 can be powered, so that the power controller 110 is powered on and the startup process is completed. Because the resistance value of the resistor R2 can be very small, the charging speed of the capacitor C1 will become very fast, so the power controller 110 can be quickly started.

[0047] In one embodiment, after the power controller 110 completes the startup, it can output a first control level to turn on the MOS tube Q1 in the charging input control unit 120. At this time, the anode level of the diode D1 is pulled down, the diode D1 is turned off, and the corresponding driving level of the charging input control unit 120 is turned off. The MOS tube Q2 also enters the off state, the charging input of the first end of the capacitor C1 is turned off, and the capacitor C1 ends the charging state. At this time, the power supply of the power controller 110 can be provided by the power supply circuit after startup. Moreover, at this time, the external power input 200 is borne by the resistor R1. Because the value of the resistor R1 can be very large, the power consumption on the resistor R1 is not small, that is, the power consumption during the power supply operation is reduced. In addition, in a specific embodiment, the diode D1 can be used to prevent the charging voltage of the capacitor C1 from being fed back to the MOS tube Q1, and the MOS tube Q1 that is turned on is connected to the negative pole of the external power supply to cause a short circuit to the capacitor C1.

[0048] like Figure 3As shown, a power supply circuit of the utility model includes the above power supply startup circuit; and a power supply output unit 300; the power supply output unit 300 is connected to the power supply controller 110, and is used to receive the second control level output by the power supply controller 110 and generate a first output voltage to power the power supply controller 110 and to generate a second output voltage as a power output. Specifically, in the power supply circuit, when the power supply controller 110 is started, the power supply output unit 300 can be controlled by the power supply controller 110 to output power. The power supply output unit 300 can provide multiple power outputs. Among them, the power supply controller 110 can be powered by the first output voltage output by the power supply output unit 300 to maintain the operation of the power supply controller 110, and the driving level can be turned off by outputting the first control level by the power supply controller 110. The second output voltage output by the power supply output unit 300 can be used as the power output of the power supply circuit to power the load.

[0049] like Figure 4 As shown, in the power supply circuit of the present utility model, the power output unit 300 includes a second diode, a third control switch and a voltage output circuit; the first input end of the voltage output circuit is connected to the external power input 200, the first end of the third control switch is connected to the second input end of the voltage output circuit, the second end of the third control switch is connected to the negative pole of the external power input 200, and the control end of the third control switch is connected to the second signal output end of the power controller 110; the anode of the second diode is connected to the first output end of the voltage output circuit, and the second output end of the voltage output circuit is connected to the negative pole of the external power input 200. Specifically, in the power output unit 300, the second diode may include a diode D2, which is used to prevent the charging voltage of the charging unit 140 from backflowing to the voltage output circuit. The power controller 110 outputs a control signal through the second signal output end to control the third control switch, so as to control the input of the voltage output circuit, and finally realize the control of the output of the voltage output circuit. Among them, the control signal output from the second signal output end of the power controller 110 can be a PWM signal, and the voltage output process of the power output unit 300 controlled by the PWM signal can adopt the current general power control process.

[0050] Optionally, the voltage output circuit includes a transformer; wherein the transformer includes an input winding, a first output winding and a second output winding; the first end of the input winding is connected to the external power input 200, and the second end of the input winding is connected to the first end of the third control switch; the first end of the first output winding is connected to the anode of the second diode, and the second end of the first output winding is connected to the negative pole of the external power input 200; the second output winding is used to generate a second output voltage. Specifically, the voltage output circuit can be a transformer. The transformer includes an input winding and multiple output windings. Among them, the third control switch is used to control the conduction or shutdown of the input winding, the first output winding is used to provide the power supply voltage required by the power controller 110, and the second output winding is used as the power output of the power circuit to provide a second power supply voltage. The second power supply voltage can be one or more, which is set according to the output requirements of the power circuit.

[0051] Optionally, the third control switch includes a third MOS tube; the drain of the third MOS tube is connected to the second end of the input winding, the source of the third MOS tube is connected to the negative electrode of the external power input 200, and the gate of the third MOS tube is connected to the second signal output end of the power controller 110. Specifically, the third control switch can be composed of MOS tubes. In a specific embodiment, the third MOS tube includes a MOS tube Q3, and the gate of the MOS tube Q3 is turned on or off according to the second control signal output by the power controller 110 to realize the conduction or shutoff of the input winding of the transformer, so as to control the power output unit 300 to work at a certain switching frequency to realize power output.

[0052] An electronic device of the utility model comprises the above power supply circuit. That is, in the electronic device, power can be supplied through the above power supply circuit. The electronic device can be understood as any electronic device that requires a power supply.

[0053] It can be understood that the above embodiments only express the preferred implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the utility model. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the utility model, the above-mentioned technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the utility model. Therefore, all equivalent changes and modifications made to the scope of the claims of the utility model should belong to the scope covered by the claims of the utility model.

Claims

1. A power startup circuit, characterized in that: include: A power controller, a charging unit, a charging input control unit and a charging input unit; The charging input control unit is connected to an external power input as well as the charging input unit and the charging unit, and is used to generate a driving level to drive the charging input unit to be turned on or off; The charging input unit is connected to the external power input and the charging unit, and is used to charge the charging unit when it is turned on, and to shut down the charging of the charging unit when it is turned off; The charging unit is connected to the power controller and is used to generate a charging voltage and supply power to the power controller through the charging voltage so as to start the power controller; The charging input control unit is also connected to the power controller, and is used to receive the first control level output by the power controller and generate the driving level or turn off the driving level.

2. The power startup circuit according to claim 1, characterized in that: The charging input control unit includes a first resistor, a first control switch, a first diode, a second resistor and a voltage regulator; The first end of the first resistor is connected to the external power input, the second end of the first resistor is connected to the first end of the first control switch and the anode of the first diode, the cathode of the first diode is connected to the charging input unit and the first end of the second resistor and the cathode of the Zener diode, the second end of the second resistor and the anode of the Zener diode are connected to the charging unit, the second end of the first control switch is connected to the negative electrode of the external power input, and the control end of the first control switch is connected to the first signal output end of the power controller.

3. The power startup circuit according to claim 2, characterized in that: The first control switch includes a first MOS tube; The source of the first MOS tube is connected to the negative electrode of the external power input, the gate of the first MOS tube is connected to the power controller, and the drain of the first MOS tube is connected to the second end of the first resistor and the anode of the first diode.

4. The power startup circuit according to claim 1, characterized in that: The charging input unit includes a third resistor and a second control switch; The first end of the third resistor is connected to the external power input, the second end of the third resistor is connected to the first end of the second control switch, the second end of the second control switch is connected to the charging unit, and the control end of the second control switch is connected to the charging input control unit for receiving the driving level.

5. The power startup circuit according to claim 4, characterized in that: The second control switch includes a second MOS tube; The drain of the second MOS tube is connected to the second end of the third resistor, the source of the second MOS tube is connected to the charging unit, and the gate of the second MOS tube is used to receive the driving level.

6. The power startup circuit according to claim 1, characterized in that: The charging unit includes a charging capacitor; The first end of the charging capacitor is connected to the power input end of the power controller, the charging input unit and the charging input control unit, and the second end of the charging capacitor is connected to the negative electrode of the external power input.

7. A power supply circuit, characterized in that: include: The power startup circuit according to any one of claims 1 to 6; and a power output unit; The power output unit is connected to the power controller, and is used to receive the second control level output by the power controller and generate a first output voltage to power the power controller and to generate a second output voltage as a power output.

8. The power supply circuit according to claim 7, characterized in that: The power output unit includes a second diode, a third control switch and a voltage output circuit; The first input terminal of the voltage output circuit is connected to the external power input, the first terminal of the third control switch is connected to the second input terminal of the voltage output circuit, the second terminal of the third control switch is connected to the negative electrode of the external power input, and the control terminal of the third control switch is connected to the second signal output terminal of the power controller; The anode of the second diode is connected to the first output terminal of the voltage output circuit, and the second output terminal of the voltage output circuit is connected to the negative electrode of the external power input.

9. The power supply circuit according to claim 8, characterized in that: The voltage output circuit includes a transformer; wherein the transformer includes an input winding, a first output winding and a second output winding; The first end of the input winding is connected to the external power input, and the second end of the input winding is connected to the first end of the third control switch; A first end of the first output winding is connected to the anode of the second diode, and a second end of the first output winding is connected to the negative electrode of the external power input; The second output winding is used to generate the second output voltage.

10. The power supply circuit according to claim 9, characterized in that: The third control switch includes a third MOS tube; The drain of the third MOS tube is connected to the second end of the input winding, the source of the third MOS tube is connected to the negative electrode of the external power input, and the gate of the third MOS tube is connected to the second signal output end of the power controller.

11. An electronic device, characterized in that: Comprising the power supply circuit as claimed in any one of claims 7 to 10.

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