Power module for suppressing electromagnetic interference

Abstract

The application relates to a power module for inhibiting electromagnetic interference, comprising an input unit; an inhibiting unit comprising a capacitor C1, an inductor L1 and a capacitor C2, the first end and the second end of the capacitor C1 are electrically connected with the input unit respectively, the first end of the inductor L1 is electrically connected with the first end of the capacitor C1, the second end of the inductor L1 is electrically connected with the first end of the capacitor C2, and the second end of the capacitor C2 is grounded; an absorbing unit comprising a capacitor C6, a resistor R1, a resistor R2 and a diode D1, the first end of the capacitor C6 is electrically connected with the first end of the resistor R1, the first end of the resistor R1 is electrically connected with the first end of the capacitor C2, the second end of the capacitor C6 is electrically connected with the second end of the resistor R1, the second end of the resistor R1 is electrically connected with the first end of the resistor R2, and the second end of the resistor R2 is electrically connected with the diode D1; and an output unit which is electrically connected with the first end of the capacitor C6 and the diode D1 respectively. The above-mentioned mode can inhibit electromagnetic interference.

Description

Technical Field

[0001] This utility model relates to the field of circuit design technology, and in particular to a power supply module for suppressing electromagnetic interference. Background Technology

[0002] The main function of a buck converter is to efficiently convert a higher input voltage into a lower, stable output voltage.

[0003] In related technologies, electromagnetic interference can easily affect the stability and reliability of buck circuits. Therefore, it is urgent to design electromagnetic interference-resistant modules in buck circuits at present. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a power module that suppresses electromagnetic interference, thereby improving the stability and reliability of the step-down circuit.

[0005] The objective of this utility model is achieved through the following technical solution: The first aspect of this application provides a power supply module for suppressing electromagnetic interference, comprising: an input unit; a suppression unit including a capacitor C1, an inductor L1, and a capacitor C2, wherein the first and second ends of the capacitor C1 are electrically connected to the input unit, the first end of the inductor L1 is electrically connected to the first end of the capacitor C1, the second end of the inductor L1 is electrically connected to the first end of the capacitor C2, and the second end of the capacitor C2 is grounded; an absorption unit including a capacitor C6, a resistor R1, a resistor R2, and a diode D1, wherein the first end of the capacitor C6 is electrically connected to the first end of the resistor R1, the first end of the resistor R1 is electrically connected to the first end of the capacitor C2, the second end of the capacitor C6 is electrically connected to the second end of the resistor R1, the second end of the resistor R1 is electrically connected to the first end of the resistor R2, and the second end of the resistor R2 is electrically connected to the diode D1; and an output unit electrically connected to the first end of the capacitor C6 and the diode D1.

[0006] The input unit includes a thermistor PZD1 and a bridge rectifier BD1. The first end of the thermistor PZD1 is used for external power supply connection, and the second end of the thermistor PZD1 is electrically connected to the bridge rectifier BD1.

[0007] It also includes a chip U1, which is electrically connected to the diode D1.

[0008] The output unit includes a transformer T1, which is electrically connected to the first terminal of the capacitor C6 and the diode D1.

[0009] The output unit also includes a diode D2, a capacitor C7, and a capacitor C8. The first end of the diode D2 is electrically connected to the transformer T1, the second end of the diode D2 is electrically connected to the first end of the capacitor C7, and the second end of the capacitor C7 is electrically connected to the first end of the capacitor C8.

[0010] The output unit also includes resistors R8 and R14. The first end of resistor R8 is electrically connected to the second end of capacitor C8, and the second end of resistor R8 is electrically connected to the first end of resistor R14.

[0011] The output unit also includes a diode D3, a capacitor C9, and a capacitor C10. The first end of the diode D3 is electrically connected to the transformer T1, the second end of the diode D3 is electrically connected to the first end of the capacitor C9, and the second end of the capacitor C9 is electrically connected to the first end of the capacitor C10.

[0012] The output unit further includes resistors R6 and R7. The first end of resistor R6 is electrically connected to the second end of capacitor C10, and the second end of resistor R6 is electrically connected to the first end of resistor R7.

[0013] The output unit also includes a connector CON1, which is electrically connected to the second end of the resistor R14 and the second end of the resistor R7, respectively.

[0014] It also includes capacitor CY3, which is electrically connected to transformer T1.

[0015] Compared with the prior art, the present invention has at least the following advantages: This application utilizes the synergistic operation of common-mode inductor L1, capacitor C1, and capacitor C2 to purify noise in the circuit, thereby achieving the purpose of electromagnetic interference reduction. Furthermore, capacitor C6, resistors R1 and R2, and diode D1 can absorb voltage and current spikes. These spikes are themselves strong sources of electromagnetic interference; absorbing them directly reduces electromagnetic interference at its source. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly described below.

[0017] Figure 1 This is a functional block diagram of a power supply module for suppressing electromagnetic interference in one embodiment of the present invention; Figure 2 This is a circuit diagram of a power supply module for suppressing electromagnetic interference according to one embodiment of the present invention. Detailed Implementation

[0018] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0019] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0020] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0021] The main function of a buck converter is to efficiently convert a higher input voltage into a lower, stable output voltage. Currently, electromagnetic interference (EMI) can easily affect the stability and reliability of buck circuits; therefore, there is an urgent need to design EMI-resistant modules within buck circuits.

[0022] To address the aforementioned issues, this application provides a power supply module that suppresses electromagnetic interference, thereby improving the stability and reliability of the step-down circuit.

[0023] The technical solutions of the embodiments of this application are described in detail below with reference to the accompanying drawings.

[0024] See Figure 1 and Figure 2A power supply module for suppressing electromagnetic interference includes: an input unit 100, a suppression unit 200, an absorption unit 300, and an output unit 400. The suppression unit 200 includes a capacitor C1, an inductor L1, and a capacitor C2. The first and second ends of capacitor C1 are electrically connected to the input unit, the first end of inductor L1 is electrically connected to the first end of capacitor C1, the second end of inductor L1 is electrically connected to the first end of capacitor C2, and the second end of capacitor C2 is grounded. The absorption unit 300 includes a capacitor C6, a resistor R1, a resistor R2, and a diode D1. The first end of capacitor C6 is electrically connected to the first end of resistor R1, the first end of resistor R1 is electrically connected to the first end of capacitor C2, the second end of capacitor C6 is electrically connected to the second end of resistor R1, the second end of resistor R1 is electrically connected to the first end of resistor R2, and the second end of resistor R2 is electrically connected to diode D1. The output unit 400 is electrically connected to the first end of capacitor C6 and diode D1.

[0025] It should be noted that input unit 100 is used to input 220V AC mains power. The combination of capacitor C1, inductor L1, and capacitor C2 acts like an electromagnetic filter, working together to purify noise in the circuit. Inductor L1 is a common-mode inductor, presenting high impedance to common-mode noise, hindering its passage. The capacitors provide a low-impedance path for high-frequency noise, bypassing it to ground. The combination of inductor and capacitor forms an attenuation path for noise at specific frequencies. Furthermore, inductor L1 primarily suppresses low-to-mid-frequency noise, while capacitors C1 and C2 primarily absorb high-frequency noise, achieving wideband noise suppression from low to high frequencies. Further, capacitor C6, resistors R1 and R2, and diode D1 can absorb voltage spikes. Voltage and current spikes in the circuit are themselves strong sources of electromagnetic interference; absorbing these spikes directly reduces electromagnetic interference at its source. Output unit 400 finally outputs 12V and 5V voltages.

[0026] See Figure 2 In one embodiment, the input unit 100 includes a thermistor PZD1 and a bridge rectifier BD1. The first end of the thermistor PZD1 is used for electrical connection to an external power supply, and the second end of the thermistor PZD1 is electrically connected to the bridge rectifier BD1.

[0027] It should be noted that after the mains power is connected to the port, the AC power is converted into DC power by the bridge rectifier diode BD1 after the surge protection function of the thermistor PZD1.

[0028] See Figure 2 In one embodiment, it also includes a chip U1, which is electrically connected to a diode D1.

[0029] It should be noted that the U1 chip is a step-down chip.

[0030] See Figure 2In one embodiment, the output unit 400 includes a transformer T1, which is electrically connected to the first terminal of the capacitor C6 and the diode D1.

[0031] It should be noted that transformer T1 is used to convert 220V voltage to 5V and 12V output. Further, bridge rectifier BD1 converts AC to DC, which is then stepped down by transformer T1 to output 5V and 12V. Specifically, when the switching transistor of chip U1 is suddenly turned off, the current in the primary winding of transformer T1 cannot change abruptly due to leakage inductance, resulting in a very high reverse induced electromotive force, i.e., a voltage spike. The polarity of this voltage spike causes diode D1 to conduct in the forward direction, opening a path for leakage inductance current. The current charges capacitor C6 through diode D1. The rise in voltage across capacitor C6 clamps the voltage across the switching transistor, limiting its peak value within a safe range. During this stage, energy is transferred from the leakage inductance to capacitor C6. When the switching transistor is turned on again, the circuit polarity is reversed, and diode D1 is cut off due to reverse bias, preventing capacitor C6 from discharging and causing a short circuit. At this time, capacitor C6 begins to discharge through resistors R1 and R2, dissipating the stored electric field energy as heat on resistors R1 and R2. Before the next turn-off cycle, the capacitor must discharge to a sufficiently low voltage so that it can effectively absorb new peak energy again.

[0032] See Figure 2 In one embodiment, the output unit 400 further includes a diode D2, a capacitor C7, and a capacitor C8. The first terminal of the diode D2 is electrically connected to the transformer T1, the second terminal of the diode D2 is electrically connected to the first terminal of the capacitor C7, and the second terminal of the capacitor C7 is electrically connected to the first terminal of the capacitor C8. Specifically, the output unit 400 further includes a resistor R8 and a resistor R14. The first terminal of the resistor R8 is electrically connected to the second terminal of the capacitor C8, and the second terminal of the resistor R8 is electrically connected to the first terminal of the resistor R14.

[0033] It should be noted that after the transformer T1 steps down the voltage, the output voltage of 12V is sent to diode D2. Diode D2 acts as a rectifier, capacitors C7 and C8 act as filters, and resistors R8 and R14 act as loads to stabilize the voltage.

[0034] See Figure 2 In one embodiment, the output unit 400 further includes a diode D3, a capacitor C9, and a capacitor C10. The first terminal of the diode D3 is electrically connected to the transformer T1, the second terminal of the diode D3 is electrically connected to the first terminal of the capacitor C9, and the second terminal of the capacitor C9 is electrically connected to the first terminal of the capacitor C10. Specifically, the output unit 400 further includes a resistor R6 and a resistor R7. The first terminal of the resistor R6 is electrically connected to the second terminal of the capacitor C10, and the second terminal of the resistor R6 is electrically connected to the first terminal of the resistor R7.

[0035] It should be noted that after the transformer T1 steps down the voltage, the output voltage of 5V is sent to diode D3. Diode D3 acts as a rectifier, capacitors C9 and C10 act as filters, and resistors R6 and R7 act as loads to stabilize the voltage.

[0036] See Figure 2 In one embodiment, the output unit 400 further includes a connector CON1, which is electrically connected to the second end of resistor R14 and the second end of resistor R7, respectively.

[0037] It should be noted that the 12V and 5V voltages are ultimately output through connector CON1.

[0038] See Figure 2 In one embodiment, a capacitor CY3 is also included, which is electrically connected to the transformer T1.

[0039] It is understandable that connecting safety capacitors on both sides of the transformer is primarily for suppressing high-frequency electromagnetic interference, especially common-mode noise, while ensuring electrical safety.

[0040] It should also be noted that the secondary feedback loop provides good electrical isolation and high-precision voltage feedback, ensuring the output voltage regulation accuracy.

[0041] The solution of this application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have different focuses; for parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. Those skilled in the art should also understand that the actions and modules involved in the specification are not necessarily essential to this application. Furthermore, it is understood that the steps in the method of this application embodiment can be adjusted, combined, and deleted according to actual needs, and the modules in the device of this application embodiment can be combined, divided, and deleted according to actual needs.

[0042] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A power supply module for suppressing electromagnetic interference, characterized in that, include: Input unit; The suppression unit includes a capacitor C1, an inductor L1, and a capacitor C2. The first and second ends of the capacitor C1 are electrically connected to the input unit, the first end of the inductor L1 is electrically connected to the first end of the capacitor C1, the second end of the inductor L1 is electrically connected to the first end of the capacitor C2, and the second end of the capacitor C2 is grounded. The absorption unit includes a capacitor C6, a resistor R1, a resistor R2, and a diode D1. The first terminal of the capacitor C6 is electrically connected to the first terminal of the resistor R1, the first terminal of the resistor R1 is electrically connected to the first terminal of the capacitor C2, the second terminal of the capacitor C6 is electrically connected to the second terminal of the resistor R1, the second terminal of the resistor R1 is electrically connected to the first terminal of the resistor R2, and the second terminal of the resistor R2 is electrically connected to the diode D1. The output unit is electrically connected to the first terminal of the capacitor C6 and the diode D1, respectively.

2. The power supply module for suppressing electromagnetic interference according to claim 1, characterized in that, The input unit includes a thermistor PZD1 and a bridge rectifier BD1. The first end of the thermistor PZD1 is used for external power supply connection, and the second end of the thermistor PZD1 is electrically connected to the bridge rectifier BD1.

3. The power supply module for suppressing electromagnetic interference according to claim 2, characterized in that, It also includes a chip U1, which is electrically connected to the diode D1.

4. The power supply module for suppressing electromagnetic interference according to claim 2, characterized in that, The output unit includes a transformer T1, which is electrically connected to the first terminal of the capacitor C6 and the diode D1.

5. The power supply module for suppressing electromagnetic interference according to claim 4, characterized in that, The output unit also includes a diode D2, a capacitor C7, and a capacitor C8. The first end of the diode D2 is electrically connected to the transformer T1, the second end of the diode D2 is electrically connected to the first end of the capacitor C7, and the second end of the capacitor C7 is electrically connected to the first end of the capacitor C8.

6. The power supply module for suppressing electromagnetic interference according to claim 5, characterized in that, The output unit also includes resistors R8 and R14. The first end of resistor R8 is electrically connected to the second end of capacitor C8, and the second end of resistor R8 is electrically connected to the first end of resistor R14.

7. The power supply module for suppressing electromagnetic interference according to claim 4, characterized in that, The output unit also includes a diode D3, a capacitor C9, and a capacitor C10. The first end of the diode D3 is electrically connected to the transformer T1, the second end of the diode D3 is electrically connected to the first end of the capacitor C9, and the second end of the capacitor C9 is electrically connected to the first end of the capacitor C10.

8. The power supply module for suppressing electromagnetic interference according to claim 7, characterized in that, The output unit further includes resistors R6 and R7. The first end of resistor R6 is electrically connected to the second end of capacitor C10, and the second end of resistor R6 is electrically connected to the first end of resistor R7.

9. The power supply module for suppressing electromagnetic interference according to claim 8, characterized in that, The output unit also includes a connector CON1, which is electrically connected to the second end of the resistor R14 and the second end of the resistor R7, respectively.

10. The power supply module for suppressing electromagnetic interference according to claim 4, characterized in that, It also includes capacitor CY3, which is electrically connected to transformer T1.

Images