CN214959276U

CN214959276U - Power supply circuit with low ripple noise input and output

Info

Publication number: CN214959276U
Application number: CN202120741092.4U
Authority: CN
Inventors: 赵宁; 董亚周; 杨宇航
Original assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Current assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Priority date: 2021-04-12
Filing date: 2021-04-12
Publication date: 2021-11-30
Anticipated expiration: 2031-04-12

Abstract

The application provides a power supply circuit with low ripple noise for input and output, which is applied to the field of power supply circuits and comprises an input filter circuit, a DC/DC converter circuit M1 and an output filter circuit; the input end of an external power supply is connected with the input filter circuit, the output end of the input filter circuit is connected with the DC/DC converter circuit M1, and the output end of the DC/DC converter circuit M1 is connected with the output filter circuit; the DC/DC converter consists of an input filter circuit, a DC/DC converter circuit and an output filter circuit; the ripple noise is enabled to be less than the requirement of 10mV ripple under the test of a 100M oscilloscope probe through an output filter circuit. The series of low-ripple noise power supply circuits and finished power supplies belong to leading levels at home and abroad, and the 7 passive devices, namely C1, C2, C3, C8, C9, L1 and L2, are used as input end filter circuits, so that the influence of the switching noise of the M1 on the input power supply can be inhibited, and the noise of the input power supply can also be inhibited from influencing the normal work of the M1.

Description

Power supply circuit with low ripple noise input and output

Technical Field

The present invention relates to power supply circuits, and particularly to a power supply circuit with low input and output ripple noise.

Background

Electronic equipment such as airborne equipment, missile-borne equipment, ships and warships and the like is internally composed of a plurality of subsystems, each subsystem uses a military power supply module, and the subsystems share an input power supply, so that power supplies of different manufacturers and different models can generate interference, serious electromagnetic interference is formed, and the subsystems work abnormally; therefore, the front section of the power module needs to be subjected to filtering processing to reduce reflection ripples and meet the requirement of electromagnetic compatibility, and the load equipment of the power module comprises gyro equipment, data link equipment and display equipment. These devices require very low output ripple noise, otherwise, the gyro precision, data transmission and display resolution are seriously affected, so the module output end of the power supply must be filtered to reduce the output ripple noise;

chinese patent CN104901519A is a multi-adaptive driving circuit and method for low ripple noise IGBT; the IGBT driving circuit of the convertible driving resistor based on the main control chip is constructed, the linear power supply conversion is utilized to realize the low-driving-voltage ripple noise, the heat consumption of the IGBT caused by overlarge driving voltage ripple is effectively reduced, the convertible driving resistor is flexibly configured through the control chip, and the IGBT driving circuit is suitable for the IGBT driving of different driving manufacturers; according to the low-ripple noise multi-adaptive driving circuit for the high-power IGBT, the driving resistor and the discharging resistor are respectively realized by connecting a plurality of resistors in parallel, the driving resistor and the discharging resistor are configured by sending control signals through the control chip, the realization mode is flexible, and the hardware structure is not changed; when the protection action occurs, the current change rate and the voltage change rate can be effectively reduced, the reliability of IGBT driving is improved, and the use risk of the IGBT is reduced;

the purpose of low ripple noise is achieved by configuring and converting the driving resistor through the control chip to adapt to different IGBT drives, the change rate of current and the change rate of voltage cannot be effectively stabilized through the filtering suppression effect, and the effect is poor.

SUMMERY OF THE UTILITY MODEL

This application aims at solving the rate of change that can't effectual come stabilization current and the rate of change of voltage through the filtering inhibit effect, and the not good technical problem of effect provides a power supply circuit of low ripple noise of input, output.

The application adopts the following technical means for solving the technical problems:

a power supply circuit with low ripple noise input and output comprises an input filter circuit, a DC/DC converter circuit M1 and an output filter circuit;

the input end of an external power supply is connected with the input filter circuit, the output end of the input filter circuit is connected with the DC/DC converter circuit M1, and the output end of the DC/DC converter circuit M1 is connected with the output filter circuit.

Further, the input filter circuit comprises a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C8, a capacitor C9, a common mode inductor L1 and a differential mode inductor L2;

the positive electrode and the negative electrode of the external power supply input end are respectively connected to the first pin and the second pin of the DC/DC converter circuit M1, the common mode inductor L1 is connected between the positive electrode and the negative electrode of the external power supply input, the differential mode inductor L2 is connected in series with the positive electrode of the external power supply input, the capacitor C1 is connected in parallel with the positive electrode and the negative electrode of the external power supply input, the capacitor C8 is connected in series with the capacitor C9 and is connected in parallel with the positive electrode and the negative electrode of the external power supply input, the ground wire is connected between the capacitor C8 and the capacitor C9, the capacitor C2 is connected in parallel between the common mode inductor L1 and the differential mode inductor L2 and is connected in parallel with the positive electrode and the negative electrode of the external power supply input, and the capacitor C3 is connected in parallel between the differential mode inductor L2 and the DC/DC converter circuit M1 and is connected with the positive electrode of the external power supply input.

Further, the output filter circuit comprises a capacitor C4, a capacitor C5, a capacitor C7, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a common mode inductor L3 and a differential mode inductor L4;

a fourth pin and a third pin of an output end of the DC/DC converter circuit M1 are respectively connected to an output positive electrode and a negative electrode of the external power supply, the capacitor C4 is connected between the output positive electrode and the negative electrode of the external power supply, the common mode inductor L3 and the differential mode inductor L4 are both connected in series with the fourth pin of the output end of the DC/DC converter circuit M1, the capacitor C5, the capacitor C10 and the capacitor C11 are located between the common mode inductor L3 and the differential mode inductor L4, the capacitor C5 is connected in parallel with a positive electrode and a negative electrode of the external power supply output, the capacitor C10 and the capacitor C11 are connected in series and connected in parallel with a positive electrode and a negative electrode of the external power supply output, the capacitor C7, the capacitor C12 and the capacitor C13 are located between the differential mode inductor L4 and the external power supply output end, the capacitor C12 is connected in series with the capacitor C13, and the capacitor C7 is connected in parallel with a positive electrode of the external power supply output, the ground wire is connected to the capacitor C10 and the capacitor C12.

Further, the differential mode inductor L2 and the differential mode inductor L4 are patch inductors.

Further, the DC/DC converter circuit M1 is for converting a DC voltage into an isolated DC voltage.

The application provides a power supply circuit with low ripple noise of input and output, which has the following beneficial effects: the DC/DC converter consists of an input filter circuit, a DC/DC converter circuit and an output filter circuit. The ripple noise is enabled to be less than the requirement of 10mV ripple under the test of a 100M oscilloscope probe through an output filter circuit. The series of low-ripple noise power supply circuits and finished power supplies belong to leading levels at home and abroad, and the 7 passive devices, namely C1, C2, C3, C8, C9, L1 and L2, are used as input end filter circuits, so that the influence of the switching noise of the M1 on the input power supply can be inhibited, and the noise of the input power supply can also be inhibited from influencing the normal work of the M1.

Drawings

Fig. 1 is a circuit diagram of an embodiment of a power supply circuit with low input and output ripple noise according to the present application.

The implementation, functional features and advantages of the present application will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is noted that the terms "comprises," "comprising," and "having" and any variations thereof in the description and claims of this application and the drawings described above are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus. In the claims, the description and the drawings of the specification of the present application, relational terms such as "first" and "second", and the like, may be used solely to distinguish one entity/action/object from another entity/action/object without necessarily requiring or implying any actual such relationship or order between such entities/actions/objects.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Referring to fig. 1, a circuit diagram of a power circuit with low input and output ripple noise according to an embodiment of the present application is shown;

the input end of an external power supply is connected with the input filter circuit, the output end of the input filter circuit is connected with the DC/DC converter circuit M1, and the output end of the DC/DC converter circuit M1 is connected with the output filter circuit;

preferably, the input filter circuit comprises a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C8, a capacitor C9, a common mode inductor L1 and a differential mode inductor L2;

Preferably, the output filter circuit comprises a capacitor C4, a capacitor C5, a capacitor C7, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a common mode inductor L3 and a differential mode inductor L4;

The differential mode inductor L2 and the differential mode inductor L4 are patch inductors.

The DC/DC converter circuit M1 converts a DC voltage into an isolated DC voltage.

Specifically, C1, C2 and C3 are input common mode filter capacitors, which can suppress low frequency common mode noise; the high-frequency filter capacitor is composed of C8 and C9 and is a Y capacitor between an input positive shell and an input negative shell; the capacitance is generally designed to be between 470pF and 10nF, and the withstand voltage is more than 1000V; the capacitor has obvious inhibition effect on ripples of a high-frequency 1M-10M frequency band.

L1 is a common mode inductor, L2 is a differential mode inductor, L1 adopts an amorphous material magnetic ring, and has the advantages of small size, large inductance and the like, and L2 can adopt an integrated patch packaged inductor to meet the requirement of a small-size number;

the 7 passive devices of C1, C2, C3, C8, C9, L1 and L2 are used as an input end filter circuit, so that the influence of the switching noise of the M1 on an input power supply can be inhibited, and the influence of the noise of the input power supply on the normal work of the M1 can be inhibited;

c4, C5 and C7 have a suppression effect on output main ripples, the output ripples are reduced to about 50mV by increasing capacitance, L3 is a common-mode inductor, L4 is a differential-mode inductor, L3 has an obvious suppression effect on low-frequency noise, L4 is a patch inductor, the suppression frequency of the inductor is more than 100M, the inductor with small capacity and high cut-off frequency can be selected, C10, C11, C12 and C13 are Y capacitors of a positive and negative output end pair shell, the capacitance is generally designed to be between 470pF and 10nF, and the withstand voltage is more than 1000V. The capacitor has obvious inhibition effect on high-frequency noise. The 8 passive devices of C4, C5, C7, L3, L4, C10, C11, C12 and C13 are used as output filter circuits, so that the output ripple of M1 can be suppressed to be below 10 mV; therefore, the purpose of reducing output ripple noise through filtering processing is achieved.

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

Claims

1. A power supply circuit with low ripple noise input and output is characterized by comprising an input filter circuit, a DC/DC converter circuit M1 and an output filter circuit;

2. The input-output low-ripple noise power supply circuit according to claim 1, wherein the input filter circuit comprises a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C8, a capacitor C9, a common-mode inductor L1, a differential-mode inductor L2;

3. The input and output low-ripple noise power supply circuit according to claim 1, wherein the output filter circuit comprises a capacitor C4, a capacitor C5, a capacitor C7, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a common-mode inductor L3 and a differential-mode inductor L4;

a fourth pin and a third pin of an output end of the DC/DC converter circuit M1 are respectively connected with an output anode and an output cathode of the external power supply, the capacitor C4 is connected between the positive pole and the negative pole of the external power supply output, the common mode inductor L3 and the differential mode inductor L4 are both connected in series with the fourth pin of the output end of the DC/DC converter circuit M1, the capacitor C5, the capacitor C10 and the capacitor C11 are positioned between the common mode inductor L3 and the differential mode inductor L4, the capacitor C5 is connected in parallel with the positive and negative poles of the external power supply output, the capacitor C10 and the capacitor C11 are connected in series and are connected in parallel with the positive and negative poles of the external power supply output, the capacitor C7, the capacitor C12 and the capacitor C13 are positioned between the differential mode inductor L4 and the external power supply output end, the capacitor C12 is connected with the capacitor C13 in series, the capacitor C7 is connected with the positive electrode and the negative electrode of the external power supply output in parallel, and the ground wire is connected to the capacitor C10 and the capacitor C12.

4. The input-output low-ripple noise power supply circuit according to claim 2, wherein the differential-mode inductor L2 is a patch inductor.

5. The input-output low-ripple noise power supply circuit according to claim 1, wherein the DC/DC converter circuit M1 is a circuit for converting a DC voltage into an isolated DC voltage.

6. The input-output low-ripple noise power supply circuit according to claim 3, wherein the differential-mode inductor L4 is a patch inductor.