Voltage stabilizing circuit for inhibiting electromagnetic interference of digital circuit

Abstract

The utility model discloses a voltage stabilizing circuit for inhibiting electromagnetic interference of a digital circuit, which comprises a digital voltage stabilizing circuit, and the input end of the digital voltage stabilizing circuit is electrically connected with an electromagnetic interference inhibiting circuit. The digital voltage stabilizing circuit comprises a triode Q1, an emitting electrode of the triode Q1 is electrically connected with one end of a resistor R1, a base electrode of the triode Q1 is electrically connected with a collector electrode of a triode Q2, a base electrode of the triode Q2 is electrically connected with one end of the resistor R1, and an emitting electrode of the triode Q2 is electrically connected with the other end of the resistor R1. According to the utility model, through the arrangement of the electromagnetic interference suppression circuit and the digital voltage stabilizing circuit, electromagnetic interference signals generated by high-frequency signals in the circuit can be effectively filtered and weakened, so that the voltage after voltage stabilization is output to other circuits or equipment without being influenced by electromagnetic interference, and the reliability of the circuit is improved. Therefore, the condition that normal work of other circuits or equipment is interfered by electromagnetic radiation is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of voltage stabilizing circuits, in particular to a voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits. Background Art

[0002] A voltage stabilizing circuit refers to a power supply circuit that can keep the output voltage basically unchanged when the input grid voltage fluctuates or the load changes. It is widely used in digital circuits. Traditional voltage stabilizing circuits lack the function of suppressing electromagnetic interference. When the digital circuit is in working state, it will generate high-frequency pulse signals. These pulse signals will generate electromagnetic radiation, thereby interfering with the normal operation of other circuits or equipment and cannot meet the use requirements. Based on the above situation, we propose a voltage stabilizing circuit that suppresses electromagnetic interference in digital circuits. Utility Model Content

[0003] The utility model aims to solve the shortcomings in the prior art and proposes a voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A voltage stabilizing circuit for suppressing electromagnetic interference of a digital circuit, comprising a digital voltage stabilizing circuit, wherein an input end of the digital voltage stabilizing circuit is electrically connected to an electromagnetic interference suppression circuit;

[0006] The digital voltage stabilizing circuit includes a transistor Q1, the emitter of the transistor Q1 is electrically connected to one end of a resistor R1, the base of the transistor Q1 is electrically connected to the collector of the transistor Q2, the base of the transistor Q2 is electrically connected to one end of the resistor R1, the emitter of the transistor Q2 is electrically connected to the other end of the resistor R1, the other end of the resistor R1 is electrically connected to one end of the resistor R2 and one end of the resistor R3, the other end of the resistor R2 is electrically connected to the other end of the resistor R3, and is electrically connected to pin 1 of a voltage regulator LM, pin 3 of the voltage regulator LM is electrically connected to the base of the transistor Q1 and the collector of the transistor Q2, pin 2 of the voltage regulator LM is electrically connected to one end of a resistor R5, the other end of the resistor R3 and the pin 1 of the voltage regulator LM are electrically connected to one end of the same resistor R4, and the other end of the resistor R5 and the other end of the resistor R4 are both grounded.

[0007] Preferably, the electromagnetic interference suppression circuit includes a resistor R6, one end of the resistor R6 is electrically connected to one end of the capacitor C1, one end of the resistor R6 is electrically connected to the capacitor C2, two ends of the capacitor C2 are electrically connected to one end of the coil L1 and one end of the coil L2 respectively, the other end of the coil L1 is electrically connected to the cathode of the diode D1 and one end of the capacitor C3, the anode of the diode D1 is electrically connected to one end of the capacitor C4 and one end of the resistor R7, one end of the resistor R7 is also electrically connected to the other end of the capacitor C1, the other end of the capacitor C3 is electrically connected to the other end of the coil L2, the other end of the coil L2 is electrically connected to the cathode of the diode D2, the anode of the diode D2 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 and the other end of the capacitor C4 are both grounded, the anode of the diode D2 is electrically connected to one end of the resistor R7, and the other end of the resistor R7 is electrically connected to the collector of the transistor Q1.

[0008] Preferably, the capacitor C2, the coil L1, the coil L2, the capacitor C3, the capacitor C4, the capacitor C5, the diode D1 and the diode D2 form a filter.

[0009] Preferably, the capacitor C1 is electrically connected between the resistor R6 and the resistor R7 to filter out high-frequency electromagnetic interference signals.

[0010] Preferably, the capacitor C2 and the capacitor C3 are both differential mode capacitors, which are used to short-circuit the differential mode interference current.

[0011] Preferably, the capacitor C4 and the capacitor C5 are used to short-circuit the common-mode interference current.

[0012] Preferably, the materials used for the coil L1 and the coil L2 are both ferrite magnetic materials with high magnetic permeability and good frequency characteristics, and the magnetic field directions of the coil L1 and the coil L2 are the same.

[0013] Compared with the existing technology, the beneficial effects of the utility model are:

[0014] 1. Through the combination of capacitor C1 and filter, the electromagnetic interference signal generated by the high-frequency signal in the circuit can be effectively filtered and weakened, and after filtering the electromagnetic interference, the voltage flowing through can be effectively stabilized through the digital voltage stabilization circuit, so that the voltage can be output stably and will not be affected by electromagnetic interference during output;

[0015] The utility model can effectively filter out and weaken the electromagnetic interference signal generated by the high-frequency signal in the circuit by setting up the electromagnetic interference suppression circuit and the digital voltage stabilization circuit, so that when the stabilized voltage is output to other circuits or equipment, it will not be affected by the electromagnetic interference, thereby reducing the situation where the electromagnetic radiation interferes with the normal operation of other circuits or equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a circuit diagram of a voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits proposed by the utility model;

[0017] Figure 2 The utility model discloses a circuit diagram of an electromagnetic interference suppression circuit in a voltage stabilizing circuit for suppressing electromagnetic interference of a digital circuit. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0019] Reference Figure 1-2 , a voltage stabilizing circuit for suppressing electromagnetic interference of a digital circuit, comprising a digital voltage stabilizing circuit, wherein an input end of the digital voltage stabilizing circuit is electrically connected to an electromagnetic interference suppression circuit;

[0020] The digital voltage stabilizing circuit includes a transistor Q1, an emitter of the transistor Q1 is electrically connected to one end of a resistor R1, a base of the transistor Q1 is electrically connected to a collector of a transistor Q2, a base of the transistor Q2 is electrically connected to one end of the resistor R1, an emitter of the transistor Q2 is electrically connected to the other end of the resistor R1, the other end of the resistor R1 is electrically connected to one end of the resistor R2 and one end of the resistor R3, the other end of the resistor R2 is electrically connected to the other end of the resistor R3, and is electrically connected to a pin 1 of a voltage regulator LM, a pin 3 of the voltage regulator LM is electrically connected to the base of the transistor Q1 and the collector of the transistor Q2, a pin 2 of the voltage regulator LM is electrically connected to one end of a resistor R5, the other end of the resistor R3 and the pin 1 of the voltage regulator LM are electrically connected to one end of the same resistor R4, and the other end of the resistor R5 and the other end of the resistor R4 are both grounded;

[0021] The electromagnetic interference suppression circuit includes a resistor R6, one end of the resistor R6 is electrically connected to one end of the capacitor C1, one end of the resistor R6 is electrically connected to the capacitor C2, two ends of the capacitor C2 are electrically connected to one end of the coil L1 and one end of the coil L2 respectively, the materials used by the coil L1 and the coil L2 are both ferrite magnetic materials with high magnetic permeability and good frequency characteristics, and the magnetic field directions of the coil L1 and the coil L2 are the same, the other end of the coil L1 is electrically connected to the negative electrode of the diode D1 and one end of the capacitor C3, wherein the capacitor C2 and the capacitor C3 are both differential mode capacitors, which are used to short-circuit the differential mode interference current, the positive electrode of the diode D1 is electrically connected to one end of the capacitor C4 and one end of the resistor R7, one end of the resistor R7 is also electrically connected to the other end of the capacitor C1, wherein the capacitor C1 is electrically connected between the resistor R6 and the resistor R7, and is used to filter out high-frequency electromagnetic interference signals, and the other end of the capacitor C3 is connected to the other end of the coil L2 The other end of the coil L2 is electrically connected to the cathode of the diode D2, the anode of the diode D2 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 and the other end of the capacitor C4 are grounded, wherein the capacitor C4 and the capacitor C5 are used to short-circuit the common-mode interference current, the anode of the diode D2 is electrically connected to one end of the resistor R7, and the other end of the resistor R7 is electrically connected to the collector of the transistor Q1, wherein the capacitor C2, the coil L1, the coil L2, the capacitor C3, the capacitor C4, the capacitor C5, the diode D1 and the diode D2 constitute a filter. The utility model can effectively filter and weaken the electromagnetic interference signal generated by the high-frequency signal in the circuit by setting the electromagnetic interference suppression circuit and the digital voltage stabilization circuit, so that when the stabilized voltage is output to other circuits or devices, it will not be affected by the electromagnetic interference, thereby reducing the situation where the electromagnetic radiation interferes with the normal operation of other circuits or devices.

[0022] Working principle: When a high-frequency signal is generated in the circuit, the high-frequency signal will flow through the conductive medium of the capacitor C1 through the resistor R6. According to the characteristics of the capacitor itself, the high-frequency signal will encounter impedance and be filtered out or weakened, which can initially reduce the impact of electromagnetic interference signals on digital circuits. At the same time, the high-frequency signal flows through the capacitor C2 and enters the coil L1 and the coil L2. Since the magnetic coupling between the coil L1 and the coil L2 is very tight, the leakage inductance will be very small. When the high-frequency signal flows through the coil L1 and the coil L2, they will cancel each other out in the magnetic core. Since the magnetic fields generated by the coil L1 and the coil L2 are in the same direction, , and thus will present a larger inductance, thereby playing the role of attenuating common-mode interference signals, and in conjunction with capacitors C4 and C5, the electromagnetic interference signals in the circuit can be effectively filtered out and weakened. When the current and voltage signals enter the digital voltage stabilization circuit, the voltage stabilizer LM will output a stabilized voltage in the circuit, and the electromagnetic interference signals generated by the high-frequency signals in the circuit can be effectively filtered out and weakened by suppressing the electromagnetic interference circuit. When the stabilized voltage is output to other circuits or equipment, it will not be affected by electromagnetic interference, thereby reducing the situation where electromagnetic radiation interferes with the normal operation of other circuits or equipment.

[0023] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A voltage stabilizing circuit for suppressing electromagnetic interference of a digital circuit, comprising a digital voltage stabilizing circuit, characterized in that: The input end of the digital voltage stabilization circuit is electrically connected to an electromagnetic interference suppression circuit; The digital voltage stabilizing circuit includes a transistor Q1, the emitter of the transistor Q1 is electrically connected to one end of a resistor R1, the base of the transistor Q1 is electrically connected to the collector of the transistor Q2, the base of the transistor Q2 is electrically connected to one end of the resistor R1, the emitter of the transistor Q2 is electrically connected to the other end of the resistor R1, the other end of the resistor R1 is electrically connected to one end of the resistor R2 and one end of the resistor R3, the other end of the resistor R2 is electrically connected to the other end of the resistor R3, and is electrically connected to pin 1 of a voltage regulator LM, pin 3 of the voltage regulator LM is electrically connected to the base of the transistor Q1 and the collector of the transistor Q2, pin 2 of the voltage regulator LM is electrically connected to one end of a resistor R5, the other end of the resistor R3 and the pin 1 of the voltage regulator LM are electrically connected to one end of the same resistor R4, and the other end of the resistor R5 and the other end of the resistor R4 are both grounded.

2. A voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 1, characterized in that: The electromagnetic interference suppression circuit includes a resistor R6, one end of the resistor R6 is electrically connected to one end of the capacitor C1, one end of the resistor R6 is electrically connected to the capacitor C2, two ends of the capacitor C2 are electrically connected to one end of the coil L1 and one end of the coil L2 respectively, the other end of the coil L1 is electrically connected to the cathode of the diode D1 and one end of the capacitor C3, the anode of the diode D1 is electrically connected to one end of the capacitor C4 and one end of the resistor R7, one end of the resistor R7 is also electrically connected to the other end of the capacitor C1, the other end of the capacitor C3 is electrically connected to the other end of the coil L2, the other end of the coil L2 is electrically connected to the cathode of the diode D2, the anode of the diode D2 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 and the other end of the capacitor C4 are both grounded, the anode of the diode D2 is electrically connected to one end of the resistor R7, and the other end of the resistor R7 is electrically connected to the collector of the transistor Q1.

3. A voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 2, characterized in that: The capacitor C2, the coil L1, the coil L2, the capacitor C3, the capacitor C4, the capacitor C5, the diode D1 and the diode D2 form a filter.

4. A voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 2, characterized in that: The capacitor C1 is electrically connected between the resistor R6 and the resistor R7 to filter out high-frequency electromagnetic interference signals.

5. The voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 2, characterized in that: The capacitor C2 and the capacitor C3 are both differential mode capacitors, which are used to short-circuit differential mode interference current.

6. The voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 2, characterized in that: The capacitor C4 and the capacitor C5 are used to short-circuit the common-mode interference current.

7. The voltage stabilizing circuit for suppressing electromagnetic interference of digital circuits according to claim 2, characterized in that: The materials used for the coil L1 and the coil L2 are both ferrite magnetic materials with high magnetic permeability and good frequency characteristics, and the magnetic field directions of the coil L1 and the coil L2 are the same.

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