Low-power diode power supply

Abstract

The utility model provides a low-power diode power supply, which comprises a soft start and overvoltage protection module for receiving input voltage and converting three-phase alternating current into direct current voltage; the boost direct current source is connected with the soft start and overvoltage protection module and used for boosting the voltage output by the soft start and overvoltage protection module so as to enable the voltage to be matched with a load diode; the voltage stabilization discharge module is connected with the boost direct current source; the load diode is connected with the voltage-stabilizing discharging module, and the voltage-stabilizing discharging module performs current-stabilizing discharging on the load diode; wherein the soft start and overvoltage protection module comprises a detection circuit and an overvoltage protection circuit, the detection circuit is used for detecting input voltage, and the overvoltage protection circuit receives a detection result of the detection circuit and stops power supply when the detection result exceeds a preset value.

Description

Technical Field

[0001] The utility model relates to the technical field of power supplies, in particular to a low-power diode power supply. Background Art

[0002] A low-power diode power supply is a circuit or device designed to provide a stable power supply for low-power electronic components (such as LEDs, sensors, small electronic devices, etc.).

[0003] Low-power diode power supplies usually input a predetermined voltage, but the supply voltage is often too high, which can damage the subsequent circuit. Utility Model Content

[0004] In view of this, the problem to be solved by the present invention is to provide a low-power diode power supply.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] According to one aspect of the present application, a low-power diode power supply is provided, including: a soft start and overvoltage protection module, which receives an input voltage and converts three-phase alternating current into a direct current voltage; a boost direct current source, which is connected to the soft start and overvoltage protection module and boosts the voltage output by the soft start and overvoltage protection module to match the load diode; a voltage-stabilizing discharge module, which is connected to the boost direct current source; and a load diode, which is connected to the voltage-stabilizing discharge module and discharges the load diode with a steady current; wherein the soft start and overvoltage protection module includes a detection circuit and an overvoltage protection circuit, the detection circuit is used to detect the input voltage, the overvoltage protection circuit receives the detection result of the detection circuit, and stops supplying power when the detection result exceeds a predetermined value.

[0007] Optionally, the detection circuit includes a first diode, a first resistor and a second resistor, the cathode of the first diode is connected to the first input end of the soft start and overvoltage protection module, the anode of the first diode is connected to the first resistor, the end of the first resistor away from the first diode is connected to the second resistor, and the end of the second resistor away from the first resistor is connected to the second input end of the soft start and overvoltage protection module.

[0008] Optionally, the overvoltage protection circuit includes a first transistor, a second transistor, and a MOS transistor; the gate of the MOS transistor is connected to the second input of the soft start and overvoltage protection module via a fourth resistor, the drain of the MOS transistor is connected to the first input of the soft start and overvoltage protection module, and the source of the MOS transistor is connected to the output of the soft start and overvoltage protection module; the base of the first transistor is connected between the first resistor and the second resistor, the emitter of the first transistor is connected to the second input of the soft start and overvoltage protection module, and the collector of the first transistor is connected to the first input of the soft start and overvoltage protection module via a third resistor and a capacitor;

[0009] The base of the second transistor is connected between the third resistor and the capacitor, the emitter of the second transistor is connected to the first input end of the soft start and overvoltage protection module, and the collector of the second transistor is connected between the gate of the MOS tube and the fourth resistor.

[0010] Optionally, the first transistor is an NPN transistor, and the second transistor is a PNP transistor.

[0011] Optionally, the steady-current discharge module includes a discharge MOS tube, the gate of the discharge MOS tube receives a drive signal provided by the feedback module, the source of the discharge MOS tube is connected to the cathode of the load diode, the drain of the discharge MOS tube is connected to the second input end of the steady-current discharge module; the anode of the load diode is connected to the first input end of the steady-current discharge module.

[0012] Optionally, it is characterized in that the low-power diode power supply further includes a sampling circuit, the sampling circuit is connected to the steady-current discharge module, and the sampling circuit is used to sample the pulse current of the steady-current discharge module.

[0013] Optionally, the feedback circuit includes a first operational amplifier; the positive input terminal of the first operational amplifier is connected to the control module, the control module provides a pulse current reference signal to the positive input terminal of the first operational amplifier, the negative input terminal of the first operational amplifier is connected to the sampling circuit, the sampling circuit provides a pulse current feedback signal to the negative input terminal of the first operational amplifier; the output terminal of the first operational amplifier is connected to the steady current discharge module, providing a discharge drive signal to the steady current discharge module; 8. In the above-mentioned low-power diode power supply, the feedback circuit also includes a second operational amplifier, the positive input terminal of the second operational amplifier is connected to the output terminal of the first operational amplifier, the negative input terminal of the second operational amplifier is connected to the voltage divider circuit, and the output terminal of the second operational amplifier is connected via the negative input terminal of the first operational amplifier.

[0014] Optionally, the voltage divider circuit includes a first voltage divider resistor and a second voltage divider resistor connected in series, and the first voltage divider resistor and the second voltage divider resistor are connected in series between a preset voltage and a ground terminal; the negative input terminal of the second operational amplifier is connected between the first voltage divider resistor and the second voltage divider resistor.

[0015] The advantages and positive effects of the utility model are:

[0016] The power supply voltage can briefly surge up to 80V. This application implements a soft-start and overvoltage protection module to prevent damage to the back-end circuit. During operation, the boost DC source boosts 28V to a voltage matching the diode load to charge the discharge energy reservoir. The regulated current discharge circuit uses a linear regulated current method to provide regulated current discharge to the diode load.

[0017] A second operational amplifier is added to the feedback circuit of the present application. When the output voltage of the first operational amplifier is less than 2.5V, the output voltage of the second operational amplifier will drop, and the voltage of the negative input terminal of the first operational amplifier will also drop, so that the output voltage of the first operational amplifier rises to 2.5V, thereby preventing the first operational amplifier from entering deep negative saturation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 A schematic diagram of the structure of a low-power diode power supply according to an embodiment of the present application is shown;

[0020] Figure 2 The schematic diagram of the circuit of the soft start and overvoltage protection module of the embodiment of the present application is shown;

[0021] Figure 3 The schematic diagram of the circuit of the steady current discharge module of the embodiment of the present application is shown;

[0022] Figure 4 A circuit schematic diagram of a feedback circuit according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a central component. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended only to describe specific embodiments and are not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] Figure 1 The schematic diagram of the structure of the low-power diode power supply of the embodiment of the present application is shown in FIG. Figure 1 As shown, the low-power diode power supply includes a soft-start and overvoltage protection module 110 , a boost DC source 120 , a voltage-stabilizing discharge module 130 , a load diode 140 and a control module 150 .

[0027] Figure 2 FIG. 1 shows a circuit schematic diagram of the soft start and overvoltage protection module 110 according to an embodiment of the present application. Figure 2 As shown, the soft start and overvoltage protection module 110 includes a detection circuit, an overvoltage protection circuit and an energy storage.

[0028] The detection circuit includes a diode Z1, a resistor R3 and a resistor R9. The cathode of the diode Z1 is connected to the first input terminal of the soft start and overvoltage protection module 110, the anode of the diode is connected to the resistor R3, the end of the resistor R3 away from the diode Z1 is connected to the resistor R9, and the end of the resistor R9 away from the resistor R3 is connected to the second input terminal of the soft start and overvoltage protection module 110.

[0029] The overvoltage protection circuit includes a transistor U5, a transistor U1, a MOS transistor U2, a resistor R2, a capacitor C1, a resistor R1, a diode Z2, a diode Z4 and a resistor R4.

[0030] The gate of the MOS transistor U2 is connected to the second input terminal of the soft-start and overvoltage protection module 110 via the resistor R4. The drain of the MOS transistor U2 is connected to the first input terminal of the soft-start and overvoltage protection module 110. The source of the MOS transistor U2 is connected to the output terminal of the soft-start and overvoltage protection module 110.

[0031] The base of transistor U5 is connected between resistor R3 and resistor R9. The emitter of transistor U5 is connected to the second input terminal of soft-start and overvoltage protection module 110. The collector of transistor U5 is connected to the first input terminal of soft-start and overvoltage protection module 110 via resistor R2 and capacitor C1. One end of resistor R1 is connected between resistor R2 and capacitor C1, and the other end is connected to the first input terminal of soft-start and overvoltage protection module 110.

[0032] The base of the transistor U1 is connected between the resistor R2 and the capacitor C1 , the emitter of the transistor U1 is connected to the first input terminal of the soft start and overvoltage protection module 110 , and the collector of the transistor U1 is connected between the gate of the MOS transistor U2 and the resistor R4 .

[0033] Diode Z2 is connected between the gate and drain of MOS transistor U2. Specifically, the anode of diode Z2 is connected to the gate of MOS transistor U2, and the cathode of diode Z2 is connected to the drain of MOS transistor U2. Diode Z4 is connected between the source and drain of MOS transistor U2. Specifically, the anode of diode Z4 is connected to the source of MOS transistor U2, and the cathode of diode Z4 is connected to the drain of MOS transistor U2.

[0034] Furthermore, the transistor U5 is, for example, an NPN transistor, and the transistor U1 is, for example, a PNP transistor.

[0035] The detection circuit is used to detect the input voltage, and the overvoltage protection circuit receives the detection result of the detection circuit and stops the power supply when the detection result exceeds a predetermined value. Specifically, when the voltage input between the first input terminal and the second input terminal exceeds 35V, the voltage on the resistor R9 exceeds 0.7V and drives the collector and emitter of the transistor U5 to conduct. At this time, R2 will drive the 0PNP transistor U1 to conduct, short-circuiting the gate of the MOS tube U2, and the MOS tube U2 will not conduct, avoiding damage to the rear pole circuit after the power supply voltage is overvoltage. When the voltage input between the first input terminal and the second input terminal is less than 35V, the voltage on the resistor R9 is less than 0.7V, and the transistor U5 is not conducting. Then the voltage on the resistor R1 is 0, and the transistor U1 is also not conducting. The gate voltage of the MOS tube U2 will pass through the capacitor C1 and the resistor R4 to perform RC discharge, slowly passing through the variable resistance area of the MOS tube U2, and using the linear area of the MOS tube U2 to perform soft start charging on the capacitors C3-C5. Avoid excessive charging current and affect the power input.

[0036] The output terminal of the soft start and overvoltage protection module 110 is connected to the boost DC source 120 . The boost DC source 120 boosts the voltage (eg, 28V) output by the soft start and overvoltage protection module 110 to a voltage matching the load diode 140 .

[0037] The output of the boost DC source 120 is connected to the steady-current discharge module 130, which performs a steady-current discharge on the load diode 140 in a linear steady-current manner. The steady-current discharge module 130 is also connected to the feedback module 170, which provides a driving signal for the steady-current discharge module 130.

[0038] Figure 3 The circuit principle diagram of the steady current discharge module of the embodiment of the present application is shown in FIG. Figure 3As shown, the steady-current discharge module 130 includes a discharge MOS transistor U6. The gate of the discharge MOS transistor U6 receives a drive signal provided by the feedback module 170. The source of the discharge MOS transistor U6 is connected to the cathode of the load diode 140. The drain of the discharge MOS transistor U6 is connected to the second input terminal of the steady-current discharge module 130. The anode of the load diode 140 is connected to the first input terminal of the steady-current discharge module 130.

[0039] Furthermore, the low-power diode power supply further includes a sampling circuit 160, which is connected to the steady-current discharge module 130 and is configured to sample the pulse current of the steady-current discharge module 130. In one embodiment, the sampling circuit 160 is, for example, a current sampling resistor connected between the drain of the discharge MOS transistor U6 and the second input terminal of the steady-current discharge module 130.

[0040] Figure 4 : shows a circuit schematic diagram of the feedback circuit of the embodiment of the present application, as shown in FIG. Figure 4 As shown, feedback circuit 170 includes operational amplifier U12B and operational amplifier U12C. The positive input of operational amplifier U12B is connected to control module 150 via resistor R122. Control module 150 provides a pulse current reference signal to the positive input of operational amplifier U12B. The negative input of operational amplifier U12B is connected to sampling circuit 160, which provides a pulse current feedback signal to the negative input of operational amplifier U12B. The output of operational amplifier U12B is connected to steady-state discharge module 130 to provide a discharge drive signal to steady-state discharge module 130.

[0041] The positive input of operational amplifier U12C is connected to the output of operational amplifier U12B. The negative input of operational amplifier U12C is connected to a voltage divider circuit. The output of operational amplifier U12C is connected to the negative input of operational amplifier U12B via diode D11. Furthermore, the voltage divider circuit includes resistors R128 and R129 connected in series. Resistors R128 and R129 are connected between the raindrop voltage and ground. The preset voltage is, for example, 15V. The negative input of operational amplifier U12C is connected between resistors R128 and R129.

[0042] Control module 150 provides an analog signal with a frequency pulse width to the positive input of operational amplifier U12B, with 2V corresponding to the maximum pulse current. When the current setting is low, the voltage difference between the positive and negative inputs of operational amplifier U12B is correspondingly small. Without the operation of operational amplifier U12C, the discharge drive signal output by the output of operational amplifier U12B would rise very slowly from 0V. This voltage is below the threshold of discharge MOSFET U6 (the threshold of discharge MOSFET U6 is approximately 2.5V), resulting in no discharge current, causing the actual discharge pulse width to be much smaller than the set pulse width. Operational amplifier U12C is added to divide the negative input of operational amplifier U12C to 2.5V. When the output voltage of operational amplifier U12B is less than 2.5V, the output voltage of operational amplifier U12C drops, causing the voltage of the negative input of operational amplifier U12B to also drop, causing the output voltage of operational amplifier U12B to rise to 2.5V, thus preventing operational amplifier U12B from entering deep negative saturation.

[0043] The power supply voltage can briefly surge up to 80V. This application implements a soft-start and overvoltage protection module to prevent damage to the back-end circuit. During operation, the boost DC source boosts 28V to a voltage matching the diode load to charge the discharge energy reservoir. The regulated current discharge circuit uses a linear regulated current method to provide regulated current discharge to the diode load.

[0044] The above embodiments of the present invention are described in detail. However, the above contents are only preferred embodiments of the present invention and should not be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of this patent.

Claims

1. A low-power diode power supply, characterized in that: include: The soft start and overvoltage protection module receives the input voltage and converts the three-phase AC power into DC voltage; A boost DC source is connected to the soft start and overvoltage protection module to boost the voltage output by the soft start and overvoltage protection module to match the load diode; A voltage-stabilizing discharge module connected to a boosted DC source; as well as The load diode is connected to the voltage stabilizing discharge module, and the voltage stabilizing discharge module discharges the load diode in a steady current; Among them, the soft start and overvoltage protection module includes a detection circuit and an overvoltage protection circuit. The detection circuit is used to detect the input voltage. The overvoltage protection circuit receives the detection result of the detection circuit and stops power supply when the detection result exceeds a predetermined value.

2. A low-power diode power supply according to claim 1, characterized in that: The detection circuit includes a first diode, a first resistor and a second resistor. The cathode of the first diode is connected to the first input end of the soft start and overvoltage protection module, the anode of the first diode is connected to the first resistor, the end of the first resistor away from the first diode is connected to the second resistor, and the end of the second resistor away from the first resistor is connected to the second input end of the soft start and overvoltage protection module.

3. A low-power diode power supply according to claim 2, characterized in that: The overvoltage protection circuit includes a first transistor, a second transistor and a MOS transistor; The gate of the MOS transistor is connected to the second input terminal of the soft start and overvoltage protection module via a fourth resistor, the drain of the MOS transistor is connected to the first input terminal of the soft start and overvoltage protection module, and the source of the MOS transistor is connected to the output terminal of the soft start and overvoltage protection module; The base of the first transistor is connected between the first resistor and the second resistor, the emitter of the first transistor is connected to the second input terminal of the soft start and overvoltage protection module, and the collector of the first transistor is connected to the first input terminal of the soft start and overvoltage protection module via the third resistor and the capacitor; The base of the second transistor is connected between the third resistor and the capacitor, the emitter of the second transistor is connected to the first input end of the soft start and overvoltage protection module, and the collector of the second transistor is connected between the gate of the MOS tube and the fourth resistor.

4. A low-power diode power supply according to claim 3, characterized in that: The first transistor is an NPN transistor, and the second transistor is a PNP transistor.

5. A low-power diode power supply according to claim 4, characterized in that: The steady-current discharge module includes a discharge MOS tube, the gate of the discharge MOS tube receives a driving signal provided by the feedback module, the source of the discharge MOS tube is connected to the cathode of the load diode, the drain of the discharge MOS tube is connected to the second input end of the steady-current discharge module; the anode of the load diode is connected to the first input end of the steady-current discharge module.

6. A low-power diode power supply according to claim 5, characterized in that The low-power diode power supply further includes a sampling circuit, which is connected to the steady-current discharge module and is used to sample the pulse current of the steady-current discharge module.

7. A low-power diode power supply according to claim 6, characterized in that: The feedback circuit includes a first operational amplifier; the positive input terminal of the first operational amplifier is connected to the control module, the control module provides a pulse current reference signal to the positive input terminal of the first operational amplifier, the negative input terminal of the first operational amplifier is connected to the sampling circuit, the sampling circuit provides a pulse current feedback signal to the negative input terminal of the first operational amplifier; the output terminal of the first operational amplifier is connected to the steady-current discharge module, providing a discharge drive signal to the steady-current discharge module.

8. A low-power diode power supply according to claim 7, characterized in that: The feedback circuit also includes a second operational amplifier, the positive input terminal of the second operational amplifier is connected to the output terminal of the first operational amplifier, the negative input terminal of the second operational amplifier is connected to the voltage divider circuit, and the output terminal of the second operational amplifier is connected via the negative input terminal of the first operational amplifier.

9. A low-power diode power supply according to claim 8, characterized in that: The voltage divider circuit includes a first voltage divider resistor and a second voltage divider resistor connected in series, and the first voltage divider resistor and the second voltage divider resistor are connected in series between a preset voltage and a ground terminal; the negative input terminal of the second operational amplifier is connected between the first voltage divider resistor and the second voltage divider resistor.

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