Multi-purpose DC regulated power supply with capacitive floating ground

Abstract

The application discloses a multi-purpose direct-current stabilized power supply adopting a capacitive suspension ground, wherein a transformer is connected with a power supply and a rectifier bridge stack, the rectifier bridge stack is connected with a first capacitor, a second capacitor and a first filter choke, the rectifier bridge stack is connected with the first capacitor, the second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor and a digital adjustment switch power supply module, the first filter choke is connected with the third capacitor, the fourth capacitor, a triode and the digital adjustment switch power supply module, the triode is connected with the digital adjustment switch power supply module, a sixth capacitor, a seventh capacitor and a first resistor respectively and is connected with a positive output end of the power supply, the triode is connected with the digital adjustment switch power supply module, the sixth capacitor, the seventh capacitor and the first resistor are connected with a negative output end of the power supply and the digital adjustment switch power supply module. The application is suitable for combination use occasions of direct-current stabilized power supplies with different voltage grades and different voltage polarities and is also suitable for other electronic instrument product test, debugging and production occasions.

Description

Technical Field

[0001] This invention relates to a multi-purpose DC regulated power supply with capacitor floating ground, belonging to the field of electronic technology. Background Technology

[0002] In the testing, debugging, and production of electronic products, it is often necessary to use a combination of DC regulated power supplies with different voltage levels and polarities. This can easily lead to problems such as incorrect power supply parameters, conflicts in test equipment resources, and large ground loop interference caused by multiple power supplies and equipment being connected to the circuit system at the same time. In particular, in some small-batch trial production product debugging and testing sites, it may be necessary to frequently change and adjust the DC regulated power supply according to different debugging objects, which places higher demands on the on-site operators. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-purpose DC regulated power supply employing capacitor-floating grounding. This addresses the problems of existing DC regulated power supplies, such as errors in power supply parameters, conflicts with test equipment resources, large size and footprint, and large grounding loop interference, thus overcoming the shortcomings of current technology. The technical solution of this invention is as follows: A multi-purpose DC regulated power supply with capacitor floating ground, comprising a transformer, the primary coil of which is connected to a 220V power supply, and the two ends of the secondary coil connected to the two input terminals of a rectifier bridge. The positive output terminal of the rectifier bridge is connected to one end of a first capacitor, a second capacitor, and a first filter choke. The negative output terminal of the rectifier bridge is connected to one end of a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, and a fifth capacitor, as well as the IN- interface of a digitally adjustable switching power supply module. The other end of the fifth capacitor is connected to the chassis. The other end of the first filter choke is connected to the other ends of the third and fourth capacitors, the collector of a transistor, and the IN+ interface of the digitally adjustable switching power supply module. The emitter of the transistor is connected to one end of the digitally adjustable switching power supply module, a sixth capacitor, a seventh capacitor, and a first resistor, and serves as the positive output terminal of the DC low-voltage power supply. The base of the transistor is connected to the OUT+ interface of the digitally adjustable switching power supply module. The other ends of the sixth capacitor, the seventh capacitor, and the first resistor are connected to the OUT- interface of the digitally adjustable switching power supply module and serve as the negative output terminal of the DC low-voltage power supply.

[0004] In the aforementioned multi-purpose DC regulated power supply with capacitor floating ground, the transformer is provided with two secondary coils, which are connected to the same circuit to form circuit A and circuit B.

[0005] In the aforementioned multi-purpose DC regulated power supply with capacitor floating ground, the negative output terminal of the DC low-voltage power supply of circuit A and the positive output terminal of the DC low-voltage power supply of circuit B are connected and then grounded; or the negative output terminal of the DC low-voltage power supply of circuit A and the positive output terminal of the DC low-voltage power supply of circuit B are connected and then the negative output terminal of the DC low-voltage power supply of circuit B is grounded.

[0006] In the aforementioned multi-purpose DC regulated power supply employing capacitor floating ground, the digitally adjustable switching power supply module includes an N-channel MOSFET. The drain of the N-channel MOSFET is connected to the IN+ interface, and the gate of the N-channel MOSFET is connected to the PMW pin of the chip. The source of the N-channel MOSFET is connected to the negative terminal of a diode and one end of a second filter choke. The positive terminal of the diode is connected to the power supply ground. The other end of the second filter choke is connected to the ninth capacitor, the tenth capacitor, and the OUT+ interface. The other ends of the ninth and tenth capacitors are connected to the power supply ground. The ADC2 pin of the chip is connected to one end of the sixth resistor and the eleventh capacitor. The other end of the eleventh capacitor is connected to the power supply ground. The other end of the sixth resistor is connected to the fourth resistor and the power output terminal of the second operational amplifier. The negative input terminal of the second operational amplifier is connected to the fourth resistor and the power output terminal of the second operational amplifier. One end of the three resistors and the other end of the fourth resistor are connected. The positive input terminal of the second operational amplifier is connected to the second resistor and the eighth capacitor, respectively. The other ends of the second resistor and the eighth capacitor are connected to the power supply ground. The other end of the third resistor is connected to the IN- interface and the fifth resistor, respectively. The other end of the fifth resistor is connected to the OUT- interface. The ADC1 pin of the chip is connected to the eleventh resistor and the twelfth capacitor, respectively. The other end of the twelfth capacitor is connected to the power supply ground. The other end of the eleventh resistor is connected to the power supply output terminal of the first operational amplifier and the tenth resistor. The negative input terminal of the first operational amplifier is connected to the other end of the tenth resistor. The positive input terminal of the first operational amplifier is connected to the seventh resistor and the eighth resistor after passing through the ninth resistor. The other end of the eighth resistor is connected to the power supply ground. The other end of the seventh resistor is connected to the emitter of the transistor.

[0007] In the aforementioned multi-purpose DC regulated power supply with capacitor floating ground, the chip is a microcontroller, model number: STM32F100.

[0008] The beneficial effects of the present invention are as follows: Compared with the prior art, due to the adoption of the above-mentioned technical solution, the DC regulated power supply of the present invention has the following characteristics:

[0009] a) The voltage regulator consists of two completely independent (0-30)V linear DC voltage regulators. It uses a modified digital switching power supply module as the control device and has functions such as precise voltage regulation, voltage and current display, and overcurrent protection.

[0010] b) The negative terminals of both power supplies are connected to the chassis via a 0.1uF capacitor (C5), forming a floating ground. The advantages are: the two power supplies can be used simultaneously as two completely independent (0-30)V power supplies, or the negative terminal of the first power supply can be connected to the positive terminal of the second power supply to form a ±(0-30)V dual power supply (e.g., ...). Figure 3 (as shown) or (0-60)V power supply (such as Figure 4 As shown), it enables multi-functional combined power supply applications, and is more versatile and easier to combine than the traditional common ground connection method;

[0011] c) The digital switching power supply module is used as the voltage reference of the linear power supply, and the output voltage is adjusted by a low-frequency high-power transistor (Q1). This has the effect of suppressing high-frequency pulses, which greatly improves the quality of the output waveform and solves the problems of large high-frequency pulse interference and large output voltage ripple in traditional switching power supplies.

[0012] d) It effectively avoids problems such as large grounding loop interference caused by multiple power supplies and devices being connected to the circuit system at the same time, thus improving the success rate of commissioning tests and the accuracy of test parameters.

[0013] The multi-purpose DC regulated power supply of the present invention is suitable for use in combination of DC regulated power supplies with different voltage levels and voltage polarities, and is also suitable for testing, debugging and production of other electronic instruments. Attached Figure Description

[0014] Figure 1 This is a circuit diagram of the present invention;

[0015] Figure 2 The circuit diagram is for a digitally controlled switching power supply module.

[0016] Figure 3 A schematic diagram of the ±(0~30)V bipolar power supply wiring;

[0017] Figure 4 This is a wiring diagram for a (0-60)V power supply. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0019] An embodiment of the present invention: a multi-purpose DC regulated power supply employing a capacitor with floating ground, such as... Figure 1-4As shown, the system includes a transformer T1. The primary coil of transformer T1 is connected to a 220V power supply, and the two ends of its secondary coil are connected to the two input terminals of a rectifier bridge D1. The positive output terminal of rectifier bridge D1 is connected to one end of the first capacitor C1, the second capacitor C2, and the first filter choke L1. The negative output terminal of rectifier bridge D1 is connected to one end of the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4, and the fifth capacitor C5, as well as the IN- interface of the digital switching power supply module. The other end of the fifth capacitor C5 is connected to the chassis. The first filter choke L1... The other end is connected to the other end of the third capacitor C3, the fourth capacitor C4, the collector of transistor Q1, and the IN+ interface of the digital switching power supply module. The emitter of transistor Q1 is connected to the digital switching power supply module, the sixth capacitor C6, the seventh capacitor C7, and one end of the first resistor R1, and serves as the positive output terminal of the DC low-voltage power supply. The base of transistor Q1 is connected to the OUT+ interface of the digital switching power supply module. The other end of the sixth capacitor C6, the seventh capacitor C7, and the first resistor R1 is connected to the OUT- interface of the digital switching power supply module and serves as the negative output terminal of the DC low-voltage power supply.

[0020] The transformer T1 has two secondary coils, which are connected to the same circuit to form circuit A and circuit B.

[0021] The negative output terminal of the DC low-voltage power supply in circuit A and the positive output terminal of the DC low-voltage power supply in circuit B are connected to ground. Figure 3 As shown, a dual power supply of ±(0~30)V is formed.

[0022] After connecting the negative output terminal of the DC low-voltage power supply of circuit A to the positive output terminal of the DC low-voltage power supply of circuit B, the negative output terminal of the DC low-voltage power supply of circuit B is grounded. Figure 4 As shown, a 0-60V power supply is formed.

[0023] The digital switching power supply module includes an N-channel MOSFET N1. The drain of N1 is connected to the IN+ interface, and the gate of N1 is connected to the PMW pin of chip IC1. The source of N1 is connected to the cathode of diode V1 and one end of the second filter choke L2. The anode of diode V1 is connected to the power supply ground. The other end of the second filter choke L2 is connected to the ninth capacitor C9, the tenth capacitor C10, and the OUT+ interface. The other ends of the ninth capacitor C9 and the tenth capacitor C10 are connected to the power supply ground. The ADC2 pin of chip IC1 is connected to the sixth resistor R6 and one end of the eleventh capacitor C11. The other end of the eleventh capacitor C11 is connected to the power supply ground. The other end of the sixth resistor R6 is connected to the fourth resistor R4 and the power output terminal of the second operational amplifier A2. The negative input terminal of the second operational amplifier A2 is connected to one end of the third resistor R3 and the other end of the fourth resistor R4. One end is connected to the positive input terminal of the second operational amplifier A2, which is connected to the second resistor R2 and the eighth capacitor C8 respectively. The other end of the second resistor R2 and the eighth capacitor C8 is connected to the power supply ground. The other end of the third resistor R3 is connected to the IN- interface and the fifth resistor R5 respectively. The other end of the fifth resistor R5 is connected to the OUT- interface. The ADC1 pin of the chip IC1 is connected to the eleventh resistor R11 and the twelfth capacitor C12 respectively. The other end of the twelfth capacitor C12 is connected to the power supply ground. The other end of the eleventh resistor R11 is connected to the power supply output terminal of the first operational amplifier A1 and the tenth resistor R10. The negative input terminal of the first operational amplifier A1 is connected to the other end of the tenth resistor R10. The positive input terminal of the first operational amplifier A1 is connected to the seventh resistor R7 and the eighth resistor R8 respectively after passing through the ninth resistor R9. The other end of the eighth resistor R8 is connected to the power supply ground. The other end of the seventh resistor R7 is connected to the emitter of the transistor Q1.

[0024] The chip IC1 is a microcontroller, model number: STM32F100.

[0025] The technical solution of this invention mainly includes the following components: a 400VA transformer T1, a D20SB80 rectifier bridge D1, a first filter choke L1 (88mH), a second filter choke L2, a high-power transistor Q1 (3DD164), a first capacitor C1 (3300uF), a second capacitor C2 (0.1uF), a third capacitor C3 (9900uF), a fourth capacitor C4 (0.1uF), a floating ground capacitor, a fifth capacitor C5 (0.1uF), a sixth capacitor C6 (220uF), a seventh capacitor C7 (0.1uF), an eighth capacitor C8, a ninth capacitor C9 (220uF), and a tenth capacitor C10 (…). 0.1uF), eleventh capacitor C11, twelfth capacitor C12, first resistor R1 (2K / 5W), second resistor R2 (1K), third resistor R3 (1K), fourth resistor R4 (10K), fifth resistor R5 (0.05 / 4W), sixth resistor R6 (1K), seventh resistor R7 (100K), eighth resistor R8 (10K), ninth resistor R9 (10K), tenth resistor R10 (10K), eleventh resistor R11 (1K), N-channel MOSFET N1 (50P06), first operational amplifier A1 (LM358H) and second operational amplifier A2 (LM358H), diode V1.

[0026] The working principle of the (0-30)V output A circuit is as follows: 220V AC power is stepped down to 34V by a 400VA transformer T1, then rectified into pulsating DC power by a D20SB80 rectifier bridge D1, and then filtered into straight DC power by a CLC composite π-type filter composed of the first filter choke L1, etc. The negative terminal of the output power supply of the D20SB80 rectifier bridge D1 is connected to the chassis through a floating ground capacitor C5 (0.1uF). The high-power transistor Q1 is used as a voltage regulator, and the reference voltage of its base is provided by the modified digital switching power supply module. The (0-30)V DC voltage can be obtained at the output terminal of the high-power transistor Q1 emitter. The working principle of the (0-30)V output B circuit is exactly the same as that of the (0-30)V output A circuit.

Claims

1. A multi-purpose DC regulated power supply employing capacitor-floating grounding, characterized in that: This includes a transformer (T1). The primary coil of the transformer (T1) is connected to a 220V power supply. The two ends of its secondary coil are connected to the two input terminals of a rectifier bridge (D1). The positive output terminal of the rectifier bridge (D1) is connected to one end of the first capacitor (C1), the second capacitor (C2), and the first filter choke (L1). The negative output terminal of the rectifier bridge (D1) is connected to one end of the first capacitor (C1), the second capacitor (C2), the third capacitor (C3), the fourth capacitor (C4), and the fifth capacitor (C5), as well as the IN-interface of the digital switching power supply module. The other end of the fifth capacitor (C5) is connected to the chassis. The first filter choke (L1)... The other end of L1 is connected to the other end of the third capacitor (C3), the fourth capacitor (C4), the collector of the transistor (Q1), and the IN+ interface of the digital switching power supply module. The emitter of the transistor (Q1) is connected to the digital switching power supply module, the sixth capacitor (C6), the seventh capacitor (C7), and one end of the first resistor (R1), and serves as the positive output terminal of the DC low-voltage power supply. The base of the transistor (Q1) is connected to the OUT+ interface of the digital switching power supply module. The other end of the sixth capacitor (C6), the seventh capacitor (C7), and the first resistor (R1) is connected to the OUT- interface of the digital switching power supply module and serves as the negative output terminal of the DC low-voltage power supply.

2. A multi-purpose DC regulated power supply with capacitor floating ground according to claim 1, characterized in that: The transformer (T1) has two secondary coils, which are connected to the same circuit, ultimately forming two circuits with completely identical structures. These two circuits are denoted as circuit A and circuit B, respectively.

3. A multi-purpose DC regulated power supply with capacitor floating ground according to claim 2, characterized in that: The negative output terminal of the DC low-voltage power supply of circuit A is connected to the positive output terminal of the DC low-voltage power supply of circuit B and then grounded; or the negative output terminal of the DC low-voltage power supply of circuit A is connected to the positive output terminal of the DC low-voltage power supply of circuit B and then the negative output terminal of the DC low-voltage power supply of circuit B is grounded.

4. A multi-purpose DC regulated power supply with capacitor floating ground according to claim 1, characterized in that: The digital switching power supply module includes an N-channel field-effect transistor (N1). The drain of the N-channel field-effect transistor (N1) is connected to the IN+ interface, and the gate of the N-channel field-effect transistor (N1) is connected to the PMW pin of the chip (IC1). The source of the N-channel field-effect transistor (N1) is connected to the negative terminal of the diode (V1) and one end of the second filter choke (L2). The positive terminal of the diode (V1) is connected to the power supply ground. The other end of the second filter choke (L2) is connected to the ninth capacitor (C9), the tenth capacitor (C10), and the OUT pin. + Interface connection: The other ends of capacitors 9 (C9) and 10 (C10) are connected to power ground; the ADC2 pin of chip (IC1) is connected to one end of resistor 6 (R6) and capacitor 11 (C11), with the other end of capacitor 11 (C11) connected to power ground; the other end of resistor 6 (R6) is connected to resistor 4 (R4) and the power output of the second operational amplifier (A2); the negative input of the second operational amplifier (A2) is connected to one end of resistor 3 (R3) and the other end of resistor 4 (R4). The positive input terminal of the second operational amplifier (A2) is connected to the second resistor (R2) and the eighth capacitor (C8), respectively. The other end of the second resistor (R2) and the eighth capacitor (C8) is connected to the power supply ground. The other end of the third resistor (R3) is connected to the IN- interface and the fifth resistor (R5), respectively. The other end of the fifth resistor (R5) is connected to the OUT- interface. The ADC1 pin of the chip (IC1) is connected to the eleventh resistor (R11) and the twelfth capacitor (C12), respectively. The other end of the twelfth capacitor (C12) is connected to the power supply ground. The power supply ground is connected to the other end of the eleventh resistor (R11), which is connected to the power supply output terminal of the first operational amplifier (A1) and the tenth resistor (R10). The negative signal input terminal of the first operational amplifier (A1) is connected to the other end of the tenth resistor (R10). The positive signal input terminal of the first operational amplifier (A1) is connected to the seventh resistor (R7) and the eighth resistor (R8) after passing through the ninth resistor (R9). The other end of the eighth resistor (R8) is connected to the power supply ground, and the other end of the seventh resistor (R7) is connected to the emitter of the transistor (Q1).

5. A multi-purpose DC regulated power supply with capacitor floating ground according to claim 4, characterized in that: The chip (IC1) is a microcontroller, model number: STM32F100.

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