Power supply circuit

Abstract

The utility model provides a power supply circuit, which is used for supplying power to a control chip and comprises a current limiting module, a voltage reduction module, a switch module, an auxiliary power supply module and a first protection module, input ends of the current-limiting module and the voltage-reducing module are respectively connected with an input power supply; the output end of the step-down module is connected with the driving end of the switch module for controlling the working state of the switch module; the output end of the current limiting module is connected to the power supply end of the control chip through the switch module and is used for supplying power to the control chip through the switch module; an input power supply is connected to the power end of the control chip through the auxiliary power supply module, and the output end of the auxiliary power supply module is connected to the driving end of the switch module through the first protection module. According to the utility model, the technical effects of quickly starting the control chip and reducing the energy consumption of the power supply circuit can be realized.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, specifically to a power supply circuit. Background Technology

[0002] In existing technology, after mains power is rectified, it needs to pass through a step-down module to supply power to the control chip. Therefore, the startup speed of the control chip is affected by the resistance value of the step-down module. If the resistance value of the step-down module is too high, it will slow down the startup speed of the control chip; if the resistance value of the step-down module is too low, it will increase the power consumption of the circuit. Therefore, existing control chip power supply circuits have a technical defect of incompatibility between the startup speed of the control chip and the power consumption of the circuit. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings and deficiencies in the prior art and provide a power supply circuit that can achieve the technical effects of quickly starting the control chip and reducing the power consumption of the power supply circuit.

[0004] One embodiment of this utility model provides a power supply circuit for supplying power to a control chip. The power supply circuit includes: a current limiting module, a step-down module, a switching module, an auxiliary power supply module, and a first protection module.

[0005] The input terminals of the current limiting module and the step-down module are respectively connected to the input power supply;

[0006] The output terminal of the step-down module is connected to the drive terminal of the switch module to control the working state of the switch module;

[0007] The output terminal of the current limiting module is connected to the power supply terminal of the control chip through a switching module, which is used to supply power to the control chip through the switching module;

[0008] The input power supply is connected to the power supply terminal of the control chip through an auxiliary power supply module, and the output terminal of the auxiliary power supply module is connected to the drive terminal of the switch module through the first protection module.

[0009] The power supply circuit of this embodiment works as follows: the input power supply provides voltage to the first connection terminal of the switching module through the current limiting module and provides voltage to the driving terminal of the switching module through the step-down module, thereby turning on the switching module. This allows the input power supply to power the control chip through the current limiting module and the turned-on switching module. The input power supply can then store energy through the auxiliary power supply module and use it to power the control chip. When the auxiliary power supply module is supplying power, it supplies power to the driving terminal of the switching module through the first protection module, increasing the voltage at the driving terminal to disconnect the switching module. At this time, no current flows through the current limiting module, and the current limiting module consumes no energy. Therefore, compared to the prior art, the power supply circuit of this invention can use a current limiting module with a smaller resistance value to improve the startup speed of the control chip. Then, with the assistance of the auxiliary power supply module to power the control chip to normal operation, the switching module is disconnected, ensuring that the current limiting module does not consume energy when the switching module is disconnected. This design balances the startup speed of the control chip and the energy consumption of the circuit, achieving the technical effects of fast control chip startup and reduced power supply circuit energy consumption.

[0010] To provide a clearer understanding of this invention, the specific embodiments of the invention will be described below in conjunction with the accompanying drawings. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the module connection of the power supply circuit according to one embodiment of the present invention.

[0012] Figure 2 This is a schematic diagram of an auxiliary power supply module in a power supply circuit according to an embodiment of the present invention.

[0013] Figure 3 This is a circuit diagram of a power supply circuit according to one embodiment of the present invention.

[0014] 1. Power supply circuit; 11. Current limiting module; 12. Step-down module; 13. Switching module; 14. Auxiliary power supply module; 142. Switching unit; 144. Discharge unit; 146. Energy storage unit; 148. Protection unit; 15. First protection module; 16. Second protection module; 3. Control chip; 5. Input power supply. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figure 1This is a power supply circuit 1 according to one embodiment of the present invention, used to supply power to the control chip 3. The control chip 3 is a chip used to implement the control functions of electronic devices, and can be a control chip 3 for smart homes, such as a dimming chip for lighting equipment, a lock chip for a smart lock, or a smart chip for a clothes dryer.

[0017] The power supply circuit 1 includes: a current limiting module 11, a step-down module 12, a switching module 13, an auxiliary power supply module 14, and a first protection module 15.

[0018] The input terminals of the current limiting module 11 and the step-down module 12 are respectively connected to the input power supply 5;

[0019] The output terminal of the step-down module 12 is connected to the drive terminal of the switch module 13 to control the working state of the switch module 13;

[0020] The output terminal of the current limiting module 11 is connected to the power supply terminal of the control chip 3 through the switch module 13, and is used to supply power to the control chip 3 through the switch module 13;

[0021] The input power supply 5 is connected to the power supply terminal of the control chip 3 through the auxiliary power supply module 14, and the output terminal of the auxiliary power supply module 14 is connected to the drive terminal of the switch module 13 through the first protection module 15.

[0022] The working principle of the power supply circuit 1 in this embodiment is as follows: the input power supply 5 provides voltage to the first connection terminal of the switch module 13 through the current limiting module 11 and provides voltage to the drive terminal of the switch module 13 through the step-down module 12, so as to turn on the switch module 13. This allows the input power supply 5 to supply power to the control chip 3 through the current limiting module 11 and the turned-on switch module 13. Then, the input power supply 5 can store energy through the auxiliary power supply module 14 and then supply power to the control chip 3 through the auxiliary power supply module 14. When the auxiliary power supply module 14 supplies power, it supplies power to the drive terminal of the switch module 13 through the first protection module 15, increasing the voltage at the drive terminal of the switch module 13 to turn off the switch module 13. At this time, no current flows through the current limiting module 11, and the current limiting module 11 consumes no energy. Therefore, compared with the prior art, the power supply circuit 1 of this utility model can use a current limiting module 11 with a smaller resistance value to improve the start-up speed of the control chip 3. Then, the auxiliary power supply module 14 assists in powering the control chip 3 to work normally. When the control chip 3 is working normally, the switch module 13 is disconnected, so that the current limiting module 11 will not consume energy when the switch module 13 is disconnected. This takes into account the characteristics of the control chip 3's start-up speed and the circuit's energy consumption, and achieves the technical effects of quickly starting the control chip 3 and reducing the energy consumption of the power supply circuit 1.

[0023] Please see Figure 2In one feasible embodiment, the auxiliary power supply module 14 includes a transformer T1, a switching unit 142, and a discharge unit 144.

[0024] The input power supply 5 is connected to the current input terminal of the transformer T1, the first current output terminal of the transformer T1 is connected to the first connection terminal of the switching unit 142, and the second current output terminal of the transformer T1 is connected to the power supply terminal of the control chip 3.

[0025] The second connection terminal of the switching unit 142 is grounded, and the driving terminal of the switching unit 142 is connected to the control terminal of the control chip 3; the first terminal of the discharge unit 144 is connected to the first connection terminal of the switching unit 142, and the second terminal of the discharge unit 144 is connected to the current input terminal of the transformer. The switching unit 142 can be a MOSFET Q2.

[0026] In this embodiment, the input power supply 5 can supply power to the control chip 3 through the current limiting module 11 and the conducting switch module 13. The working principle of the input power supply 5 storing energy through the auxiliary power supply module 14 is as follows: The input power supply 5 supplies power to the control chip 3 through the current limiting module 11 and the conducting switch module 13 to start the control chip 3. The control terminal of the control chip 3 outputs a first control signal to the drive terminal of the switch unit 142, causing the switch unit 142 to conduct. At this time, the current output by the input power supply 5 flows to ground through the transformer T1 and the conducting switch unit 142. When the current output by the input power supply 5 passes through the transformer, the transformer T1 stores energy. Then, the control terminal of the control chip 3 outputs a second control signal to the drive terminal of the switch unit 142, causing the switch unit 142 to disconnect. At this time, the first current output terminal and the second current output terminal of transformer T1 will release the energy stored in the transformer. That is, the current output from the first current output terminal of transformer T1 is discharged to the current input terminal of transformer T1 through the discharge unit 144, and the current output from the second current output terminal of transformer T1 is discharged to the power supply terminal of control chip 3 to supply power to the power supply terminal of control chip 3, so that control chip 3 can remain in working state. The control terminal of control chip 3 continuously switches the output of the first control signal and the second control signal to the drive terminal of switch unit 142, that is, repeats the process of transformer T1 storing energy and transformer T1 supplying power to control chip 3. When transformer T1 stores energy, the input power supply 5 can supply power to control chip 3 through current limiting module 11 and the conducting switch module 13.

[0027] In this embodiment, the transformer T1 can be used to store energy and provide auxiliary power to the control chip 3.

[0028] Please see Figure 3In one feasible embodiment, the control chip 3 may be IC1, and the transformer T1 includes a main winding N1 and an auxiliary winding N3.

[0029] The input power supply 5 is connected to the input terminal of the main winding N1, the output terminal of the main winding N1 is connected to the first connection terminal of the switching unit 142, and the output terminal of the auxiliary winding N3 is connected to the power supply terminal of the control chip 3.

[0030] When the switching unit 142 is turned on, the current output by the input power supply 5 reaches the first end of the main winding N1, and the main winding N1 and the auxiliary winding N3 will store energy based on electromagnetic induction. When the switching unit 142 is turned off, the input power supply 5 stops outputting current to the first end of the main winding N1, the second end of the main winding N1 will output the stored energy as current based on electromagnetic induction to be transmitted to the first end of the main winding N1 through the discharge unit 144. At this time, the third end of the auxiliary winding N3 will output the stored energy as current based on electromagnetic induction to supply power to the power supply terminal of the control chip 3.

[0031] In this embodiment, the transformer can store energy and supply power through the main winding N1 and the auxiliary winding N3.

[0032] In other embodiments, the transformer may further include a secondary winding N2 that supplies power to other electrical units, wherein the secondary winding N2 stores energy and outputs the stored energy as current to supply power to other electrical units in the same manner as the auxiliary winding N3.

[0033] In one feasible embodiment, the auxiliary power supply module 14 further includes an energy storage unit 146, the first connection terminal of the switching unit 142 is connected to the first terminal of the energy storage unit 146, and the second terminal of the energy storage unit 146 is connected to the current input terminal of the transformer.

[0034] The energy storage unit 146 can effectively prevent voltage surges at the first connection terminal of the switching unit 142, thereby reducing the impact of voltage changes on the switching unit 142. Furthermore, the energy storage unit 146 can filter and store the current output from the second current output terminal of the transformer. The energy stored in the energy storage unit 146 can be output as current and transmitted to the current input terminal of the transformer via the discharge unit 144 to release the energy stored in the energy storage unit 146. The energy storage unit 146 may include a capacitor with filtering and energy storage functions.

[0035] In one feasible embodiment, the auxiliary power supply module 14 further includes a protection unit 148, and the first connection terminal of the switching unit 142 is connected to the first terminal of the energy storage unit 146 through the protection unit 148.

[0036] To prevent current backflow from the first terminal of the energy storage unit 146 to the first connection terminal of the switching unit 142 when the voltage at the first terminal of the energy storage unit 146 is higher than the voltage at the first connection terminal of the switching unit 142, a protection unit 148 is used to limit the current flow between the first terminal of the energy storage unit 146 and the first connection terminal of the switching unit 142. Specifically, the protection unit 148 includes a first diode D3, the anode of which is connected to the first connection terminal of the switching unit 142, and the cathode of which is connected to the first terminal of the energy storage unit 146. The first diode D3 of the protection unit 148 can improve the safety of the circuit.

[0037] In this embodiment, the first diode D3 of the protection unit 148 can improve the operational safety of the circuit.

[0038] Please see Figure 3 In one feasible embodiment, the input power supply 5 can be a power supply circuit 1 including a rectifier module BD1 and a filter capacitor CE1. The rectifier module BD1 includes a first input terminal, a second input terminal, a third input terminal, and an output terminal. The first input terminal of the rectifier module BD1 is connected to the live wire, the second input terminal is connected to the neutral wire, and the output terminal of the rectifier module BD1 is connected to the third input terminal via the filter capacitor. The output terminal of the rectifier module BD1 is grounded via the filter capacitor, and the output of the rectifier module BD1 is the input power supply 5. The switching module 13 can be a MOSFET Q1.

[0039] In one feasible embodiment, the first protection module 15 includes a Zener diode ZD1, the output terminal of the auxiliary power supply module 14 is connected to the anode of the Zener diode ZD1, and the cathode of the Zener diode ZD1 is connected to the drive terminal of the switching module 13.

[0040] Among them, the Zener diode ZD1 can improve the voltage stability of the drive terminal of the switching module 13. Moreover, when the voltage of the power output terminal of the auxiliary power supply module 14 is greater than the voltage of the drive terminal of the switching module 13, the Zener diode ZD1 is forward-biased to increase the voltage of the drive terminal of the switching module 13 and disconnect the switching module 13. At this time, no current flows through the current limiting module 11 and the current limiting module 11 consumes no energy.

[0041] In this example, by using the Zener diode ZD1, when the power output terminal of the auxiliary power supply module 14 supplies power to the control chip 3, the switching module 13 can be automatically turned on to reduce the energy consumption caused by the current limiting module 11, thereby reducing the energy consumption of the circuit.

[0042] In one feasible embodiment, the power supply circuit 1 further includes a second protection module 16, the first end of which is connected to the power output terminal of the auxiliary power supply module 14, and the second end of which is connected to the power supply terminal of the control chip 3.

[0043] In order to prevent current backflow from occurring when the power supply terminal of the control chip 3 outputs current to the power output terminal of the auxiliary power supply module 14 while the auxiliary power supply module 14 is storing energy, the second protection module 16 can limit the current flow between the power output terminal of the auxiliary power supply module 14 and the power supply terminal of the control chip 3. Therefore, the second protection module 16 can include a second diode D1, the anode of the second diode D1 is the first terminal of the second protection module 16, and the cathode of the second diode D1 is the second terminal of the second protection module 16.

[0044] In this embodiment, the second diode D1 of the second protection module 16 can improve the operational safety of the circuit.

[0045] In one feasible embodiment, the power supply circuit 1 further includes a filtering module, the first end of which is connected to the power supply terminal of the control chip 3, and the second end of which is grounded. The filtering module may include a capacitor CE2.

[0046] In this embodiment, the power supply to the control chip 3 can be stably provided through the filtering module.

[0047] In one feasible embodiment, the current limiting module 11 includes a plurality of current limiting resistors connected in series; the input power supply 5 is connected to the power supply terminal of the control chip 3 through the plurality of current limiting resistors connected in series and the switch module 13. The plurality of current limiting resistors connected in series may include resistors R3 and R4.

[0048] The step-down module 12 includes several step-down resistors connected in series; the input power supply 5 is connected to the drive terminal of the switch module 13 through these several step-down resistors. The several step-down resistors connected in series may include resistors R1 and R2.

[0049] In this embodiment, the input power supply 5 can be current-limited and voltage-reduced by the series current-limiting resistor and the series voltage-reducing resistor, so that the first connection terminal and the driving terminal of the switching module 13 can be smoothly turned on due to the potential difference.

[0050] In one feasible embodiment, the power supply circuit 1 further includes a detection module, which includes a first input terminal, a first output terminal, and a second output terminal. The first input terminal of the detection module is connected to the power output terminal of the auxiliary power supply module 14, the first output terminal of the detection module is connected to the detection terminal of the control chip 3, and the second output terminal of the detection module is grounded. Through the detection module, the control chip 3 can detect the power information output by the power output terminal of the auxiliary power supply module 14, and control the switching unit 142 to turn on and off according to the power information. The detection module may include resistors R7 and R8, wherein the first end of resistor R7 is the first input terminal of the detection module, the second end of resistor R7 is the first output terminal of the detection module, the first end of resistor R8 is connected to the second end of resistor R7, and the second end of resistor R8 is the second output terminal of the detection module.

[0051] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A power supply circuit, characterized in that, include: Current limiting module, step-down module, switching module, auxiliary power supply module, and first protection module; The input terminals of the current limiting module and the step-down module are respectively connected to the input power supply; The output terminal of the step-down module is connected to the drive terminal of the switch module to control the working state of the switch module; The output terminal of the current limiting module is connected to the power supply terminal of the control chip through a switching module, which is used to supply power to the control chip through the switching module; The input power supply is connected to the power supply terminal of the control chip through an auxiliary power supply module, and the output terminal of the auxiliary power supply module is connected to the drive terminal of the switch module through the first protection module.

2. The power supply circuit according to claim 1, characterized in that: The auxiliary power supply module includes a transformer, a switching unit, and a discharge unit; The input power supply is connected to the current input terminal of the transformer, the first current output terminal of the transformer is connected to the first connection terminal of the switching unit, and the second current output terminal of the transformer is connected to the power supply terminal of the control chip. The second connection terminal of the switching unit is grounded, and the driving terminal of the switching unit is connected to the control terminal of the control chip; the first terminal of the discharge unit is connected to the first connection terminal of the switching unit, and the second terminal of the discharge unit is connected to the current input terminal of the transformer.

3. The power supply circuit according to claim 2, characterized in that: The transformer includes a main winding and an auxiliary winding; The input power supply is connected to the input terminal of the main winding, the output terminal of the main winding is connected to the first connection terminal of the switching unit, and the output terminal of the auxiliary winding is connected to the power supply terminal of the control chip.

4. The power supply circuit according to claim 2, characterized in that: The auxiliary power supply module also includes an energy storage unit. The first connection terminal of the switching unit is connected to the first terminal of the energy storage unit, and the second terminal of the energy storage unit is connected to the current input terminal of the transformer.

5. The power supply circuit according to claim 4, characterized in that: The auxiliary power supply module also includes a protection unit, and the first connection terminal of the switching unit is connected to the first terminal of the energy storage unit through the protection unit.

6. The power supply circuit according to claim 5, characterized in that: The protection unit includes a first diode, the anode of which is connected to the first connection terminal of the switching unit, and the cathode of which is connected to the first terminal of the energy storage unit.

7. The power supply circuit according to claim 1, characterized in that: The first protection module includes a Zener diode, the output terminal of the auxiliary power supply module is connected to the anode of the Zener diode, and the cathode of the Zener diode is connected to the drive terminal of the switching module.

8. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes a second protection module, the first end of which is connected to the power output terminal of the auxiliary power supply module, and the second end of which is connected to the power supply terminal of the control chip.

9. The power supply circuit according to claim 8, characterized in that: The second protection module includes a second diode, with a first end of the second protection module connected to the anode of the second diode and the cathode of the second diode connected to the power supply terminal of the control chip.

10. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes a filter module, the first end of which is connected to the power supply terminal of the control chip, and the second end of which is grounded.

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