Switching power supply circuit for reducing ripple voltage

Abstract

The utility model discloses a switching power supply circuit for reducing ripple voltage, which relates to the technical field of circuit design, and comprises capacitors C1-C4, a diode D1, a power supply chip U1 and an inductor L1, the capacitor C1 is introduced to be connected with the diode D1 and a filter capacitor C2, a pin pin1 of the power supply chip U1 is connected with the diode D1 and the capacitor C2, and a pin pin2 of the power supply chip U1 is connected with the capacitor C2. A pin pin2 of the power supply chip U1 is connected to a pin pin3 of the power supply chip U1 through a resistor R1 and a capacitor C3, the pin pin3 of the power supply chip U1 is connected with the ground, a pin pin4 of the power supply chip U1 is connected with a capacitor C4 and an inductor L1 for filtering layer by layer, the problem that the ripple voltage in a traditional switching power supply is large is solved, the improved circuit can effectively reduce the ripple voltage output by the switching power supply, and the service life of the switching power supply is prolonged. The stability and reliability of the power supply are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit design, and more specifically to a switching power supply circuit for reducing ripple voltage. Background Art

[0002] At present, the switching power supply is a common power supply with the advantages of high efficiency, stability and reliability, and is widely used in communications, computers, industry and other fields. However, when the switching power supply outputs voltage, a ripple voltage of a certain amplitude will appear. This is caused by the high-frequency oscillation generated by the oscillation circuit composed of capacitors and inductors in the filter circuit at the output end of the switching power supply. In some applications, due to the influence of circuit noise and other interference factors, the ripple voltage may have a negative impact on the operation of the system. At the same time, a ripple voltage with a certain amplitude will also bring additional pressure to electronic components and reduce the service life of the circuit. Therefore, how to effectively reduce the ripple voltage of the switching power supply and improve the stability and purity of the output signal has become one of the key technologies that restrict the performance of the switching power supply. The development of an effective switching power supply ripple voltage improvement circuit has important practical application significance.

[0003] Therefore, how to reduce the ripple voltage of the switching power supply is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0004] In view of this, the utility model provides a switching power supply circuit for reducing ripple voltage, which helps to reduce the ripple voltage of the switching power supply, improve the stability and purity of the output signal, and improve the circuit.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A switching power supply circuit for reducing ripple voltage, comprising: a power chip U1, a capacitor C1, a diode D1, a capacitor C2, a resistor R1, a capacitor C3, a capacitor C4 and an inductor L1;

[0007] The capacitor C1 is connected to the power chip U1 through the diode D1 and the capacitor C2 in parallel; the pin pin2 of the power chip U1 is connected to the pin pin3 of the power chip U1 through the resistor R1 and the capacitor C3 in turn, and the pin pin3 of the power chip is grounded; the pin pin4 of the power chip U1 is connected to the capacitor C4 and the inductor L1.

[0008] The technical effect of the above technical solution is that the pin 3 of the power chip U1 is grounded to adjust the output wave voltage;

[0009] Preferably, the capacitor C1 is an electrolytic capacitor, the positive electrode of the capacitor C1 is connected to the first parallel node of the diode D1 and the capacitor C2, and the negative electrode is grounded.

[0010] Preferably, the second parallel node between the diode D1 and the capacitor C2 is connected to a pin pin1 of the power chip U1.

[0011] Preferably, the capacitor C4 is an electrolytic capacitor; the pin pin4 of the power chip is connected to the positive electrode of the capacitor C4 and the fourth pin of the inductor L1, and the negative electrode of the capacitor C4 is connected to the first pin of the inductor L1 and the ground.

[0012] Preferably, the capacitor C1 and the capacitor C3 are connected to a power ground, and the capacitor C4 is connected to a signal ground.

[0013] Preferably, the second pin and the third pin of the inductor L1 output direct current.

[0014] It can be seen from the above technical solutions that, compared with the prior art, the utility model discloses a switching power supply circuit for reducing ripple voltage, which reduces voltage fluctuations and achieves very small ripple voltage through step-by-step filtering of capacitors, diodes, power chips, capacitors, and inductors, thereby ensuring a smooth DC voltage output, improving product stability, and extending product service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0016] Figure 1 The accompanying drawing is a schematic diagram of the structure of a switching power supply circuit for reducing ripple voltage provided by the utility model. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] Example 1

[0019] The utility model discloses a switching power supply circuit for reducing ripple voltage, which is a switching power supply circuit for reducing ripple voltage. Figure 1 As shown, the switching power supply high-voltage output no-load power consumption improvement circuit of this embodiment includes: capacitor C1, diode D1, capacitor C2, power chip U1, resistor R1, capacitor C3, capacitor C4 and inductor L1.

[0020] The positive electrode of capacitor C1 is connected to diode D1 and capacitor C2, and the negative electrode is grounded; pin 1 of power chip U1 is connected to diode D1 and capacitor C2, pin 2 of power chip is connected to resistor R1, capacitor C3, and pin 3 of power chip in sequence, and the connection node between capacitor C3 and pin 3 is grounded together; pin 4 of power chip U1 is connected to capacitor C4 and inductor L1, the positive electrode of capacitor C4 is connected to pin 4 and the fourth pin of inductor L1, and the negative electrode of capacitor c4 and the first pin of inductor L1 are grounded.

[0021] Furthermore, the diode D1 and the capacitor C2 are connected in parallel, the positive electrode of the capacitor C1 is connected to the first parallel node, that is, connected to the anode end of the diode D1, and the pin pin1 of the power chip U1 is connected to the second parallel node, that is, connected to the cathode end of the diode D1.

[0022] Furthermore, the second pin and the third pin of the inductor L1 output direct current, and serve as a negative electrode and a positive electrode of a direct current power supply, respectively.

[0023] Furthermore, the negative electrode of the capacitor C1 and the pin 3 of the power chip U1 are both connected to the power ground, and the negative electrode of the capacitor C4 and the first pin of the inductor L1 are both connected to the signal ground.

[0024] Furthermore, the power chip U1 adopts OB2362MP components; the inductor L1 is a common mode inductor.

[0025] Example 2

[0026] Based on the above embodiments, on the one hand, the working principle of the switching power supply circuit for reducing the ripple voltage is as follows: when the switching power supply inputs a voltage, it is first filtered by the input capacitor C1, then rectified by the diode D1 and the capacitor C2, and enters the inside of the power supply chip U1 through the pin 1 of the power supply chip U1. After the power supply chip U1 is rectified by the internal voltage comparator, it is output through the pin 2 of the power supply chip U1, filtered by the resistor R1 and the capacitor C3, and grounded together with the pin 3 of the power supply chip U1. The rectified and filtered voltage is output through the pin 4 of the power supply chip U1. The voltage output from the pin 4 of the power supply chip U1 is filtered by the capacitor C4 and the inductor L1 to output a stable and smooth DC power.

[0027] In summary, in this embodiment, the capacitor, diode, power supply chip and inductor are used for step-by-step filtering to adjust the Wenbo voltage, thereby ensuring a stable DC voltage output.

[0028] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0029] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A switching power supply circuit for reducing ripple voltage, characterized in that: include: Power chip U1, capacitor C1, capacitor C2, capacitor C3, capacitor C4, diode D1, resistor R1 and inductor L1; The capacitor C1 is connected to the power chip U1 through the diode D1 and the capacitor C2 in parallel; the pin pin2 of the power chip U1 is connected to the pin pin3 of the power chip U1 through the resistor R1 and the capacitor C3 in sequence, and the pin pin3 of the power chip is grounded; the pin pin4 of the power chip U1 is connected to the capacitor C4 and the inductor L1.

2. A switching power supply circuit for reducing ripple voltage according to claim 1, characterized in that: The capacitor C1 is an electrolytic capacitor, the positive electrode of the capacitor C1 is connected to the first parallel node of the diode D1 and the capacitor C2, and the negative electrode of the capacitor C1 is grounded.

3. The switching power supply circuit for reducing ripple voltage according to claim 1, characterized in that: A second parallel node of the diode D1 and the capacitor C2 is connected to a pin pin1 of the power chip U1 .

4. The switching power supply circuit for reducing ripple voltage according to claim 1, characterized in that: The capacitor C4 is an electrolytic capacitor; the pin pin4 of the power chip is connected to the positive electrode of the capacitor C4 and the fourth pin of the inductor L1, and the negative electrode of the capacitor C4 is connected to the first pin of the inductor L1 and the ground.

5. The switching power supply circuit for reducing ripple voltage according to claim 1, characterized in that: The capacitor C1 and the capacitor C3 are connected to a power ground, and the capacitor C4 is connected to a signal ground.

6. The switching power supply circuit for reducing ripple voltage according to claim 1, characterized in that: The second pin and the third pin of the inductor L1 output direct current.

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