Multifunctional input surge suppression circuit

Abstract

The utility model relates to the technical field of DC input switching power supply circuits, and provides a multifunctional input surge suppression circuit, which comprises a chip IC1, a clamping diode D2, an undervoltage and overvoltage detection circuit, an input anti-surge diode D1, a current detection resistor R1, MOS transistors Q1 and Q2, a power setting resistor R6 and a charging time setting resistor C3. The IC1 is responsible for monitoring input voltage in real time and sending a driving signal to control the Q1 and the Q2 when conditions are met, so that accurate control over the circuit is achieved. The circuit has the functions of overvoltage protection, reverse connection protection and short circuit protection, and stable operation of the circuit under various abnormal conditions is ensured. According to the design, multiple protection mechanisms including surge suppression, overvoltage and undervoltage protection and short circuit protection are integrated, the reliability of the circuit is remarkably improved, and the service life of the circuit is remarkably prolonged. In addition, a working auxiliary power supply of the relay is omitted, the circuit design is simplified, the size is reduced, and power consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of direct current input switching power supply circuits, in particular to a multifunctional input surge suppression circuit. Background Art

[0002] All the DC input switching power supply surge suppression circuits on the market mostly use relays or MOS tubes. Relays cannot effectively suppress the large current caused by the voltage difference across the contacts, the contact life problem, the relay temperature resistance problem, the large current generated by the sudden short circuit of the subsequent stage, and it is easy to burn the contacts, etc.

[0003] The surge suppression circuit using relays has a single function and cannot meet all the requirements of the downstream electrical equipment. The surge current suppression circuit using MOS tubes generally does not detect the current or the voltage at both ends, and its opening and closing are completely uncontrolled. Utility Model Content

[0004] In order to solve the problems existing in the background technology, the utility model provides a multifunctional input surge suppression circuit, comprising:

[0005] Chip IC1 is used to detect the input voltage and send out a driving signal;

[0006] Clamping diode D2, connected to the output of IC1;

[0007] An undervoltage detection circuit includes resistors R3 and R5;

[0008] An overvoltage detection circuit, including resistors R2 and R4;

[0009] Input surge protection diode D1;

[0010] Input current detection resistor R1;

[0011] Two MOS tubes Q1 and Q2 that form switches;

[0012] Power setting resistor R6;

[0013] Charging time setting resistor C3.

[0014] In a preferred solution, IC1 sends a driving signal when the input terminal voltage meets the conditions, detects the input terminal current through R1, and drives Q1 and Q2 according to the preset starting power.

[0015] In a preferred solution, when the input is over-voltage, IC1 can detect and prevent Q1 and Q2 from conducting.

[0016] In a preferred solution, when the input terminal is reversely connected, IC1 does not work, resulting in Q1 and Q2 being non-conductive.

[0017] In a preferred solution, when the subsequent switching power supply device is short-circuited, IC1 can collect abnormal current and pull down the Q1 and Q2 signals to prevent damage.

[0018] The beneficial effects achieved by the utility model are:

[0019] The input surge suppression circuit of the utility model provides significant benefits in protecting the power supply circuit and improving the circuit stability and reliability through its innovative design, while also simplifying the design, reducing the cost, and improving the market competitiveness of the product, which is specifically manifested in:

[0020] First, surge current suppression: The circuit uses chip IC1 to detect the voltage level at the input end, and sends a drive signal when the voltage that meets the conditions is detected, so that the circuit can effectively suppress the surge current that may occur at the input end, thereby protecting the circuit from damage by transient high-voltage current. If the input end is reversely connected, IC1 will not work, causing the MOS tubes Q1 and Q2 connected in the circuit to not be turned on. This design avoids damage to the circuit that may be caused by reverse connection of the input end.

[0021] Second, to ensure that the circuit operates within a safe voltage range, an undervoltage detection circuit and an overvoltage detection circuit are integrated into the circuit. These two circuits are composed of resistors R3 and R5, and resistors R2 and R4, respectively, and they work together to prevent abnormal voltage from causing damage to the circuit.

[0022] Third, the circuit also has a short-circuit protection function. When a short circuit occurs in the subsequent switching power supply device, IC1 can detect the abnormal current and respond quickly, cutting off the circuit by pulling down the signals of MOS tubes Q1 and Q2, thereby preventing further damage caused by the short circuit.

[0023] Fourth, by eliminating the auxiliary power supply for the relay, the circuit design is simplified. This simplification not only reduces the need for external components, but also makes the entire circuit smaller, making it easier to integrate and deploy. Since the circuit draws power directly from the electrical equipment, there is almost no additional power consumption. In addition, the use of MOS tubes as switching devices can significantly improve the life and temperature resistance of the circuit compared to traditional relays. This circuit design integrates a variety of protection functions, including surge suppression, over-voltage and under-voltage protection, and short-circuit protection. The integration of these functions enables the circuit to operate stably and reliably in the face of different power supply problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the utility model. DETAILED DESCRIPTION

[0025] The technical solution of the utility model will be clearly and completely described below in conjunction with the drawings in the utility model. In addition, the forms of the various structures recorded in the following embodiments are merely illustrative, and the utility model is not limited to the various structures recorded in the following embodiments. All other implementations obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the utility model.

[0026] Reference Figure 1 The multifunctional input surge suppression circuit of the utility model includes a microcontroller IC1: as the core of the circuit, it is responsible for detecting the input voltage and sending a driving signal. Clamping diode D2: connected to the output of IC1, used to protect IC1 from the influence of voltage surges. Undervoltage detection circuit: composed of resistors R3 and R5, used to detect whether the input voltage is lower than the set safety threshold. Overvoltage detection circuit: composed of resistors R2 and R4, used to detect whether the input voltage exceeds the set safety threshold. Input surge protection diode D1: used to provide protection when the input voltage is abnormal. Input current detection resistor R1: used to detect the current passing through the input terminal. MOS tubes Q1 and Q2: constitute the switch part of the circuit, and control the conduction and disconnection of the circuit according to the driving signal of IC1. Power setting resistor R6: used to set the starting power of the circuit. Charging time setting resistor C3: used to set the charging time before MOS tubes Q1 and Q2 are fully turned on.

[0027] When the circuit is plugged in, the microcontroller IC1 gets the power first and starts to work. The main task of IC1 is to monitor the voltage level at the input to ensure that it is within the safe operating range.

[0028] The voltage detection circuit inside IC1 continuously detects the input voltage. Once the input voltage reaches the preset safe operating voltage range, pin 10 of IC1 sends a drive signal.

[0029] The driving signal is transmitted to MOS tubes Q1 and Q2. After receiving the signal, Q1 and Q2 are slowly turned on. During this process, IC1 controls the turning-on speed of the MOS tube to avoid impact on the circuit due to sudden current changes.

[0030] At the same time, IC1 monitors the current flowing through the circuit through the input current detection resistor R1. The voltage drop across R1 is proportional to the current passing through. IC1 can calculate the actual current based on this voltage drop and compare it with the preset startup power.

[0031] IC1 adjusts the intensity of the driving signal through the power setting resistor R6 according to the detected current information and the preset starting power, thereby controlling the conduction degree of Q1 and Q2. In addition, the charging time setting resistor C3 cooperates with IC1 to ensure that the MOS tube is fully turned on after the set charging time is reached.

[0032] After the set charging time, if everything is normal, IC1 makes Q1 and Q2 fully conductive, and the circuit will enter the normal working state. At this time, the circuit can provide stable power supply for the subsequent electrical equipment.

[0033] If during power-on or operation, IC1 detects that the input voltage exceeds the preset safety threshold, that is, an overvoltage condition occurs, IC1 will block the issuance of the drive signal, thereby preventing Q1 and Q2 from turning on and preventing the circuit from being damaged due to overvoltage.

[0034] If the input terminal is reversed, IC1 will not be able to obtain the correct voltage signal, so no driving signal is issued, causing Q1 and Q2 to remain in the off state, thus avoiding possible circuit damage caused by reverse input terminal connection.

[0035] Under normal operating conditions, if a short circuit occurs in the downstream switching power supply device, IC1 can detect the abnormally high current through R1. Once a short circuit condition is detected, IC1 responds quickly by pulling down the drive signal to turn off Q1 and Q2, cutting off the power supply to prevent damage caused by the short circuit.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multifunctional input surge suppression circuit, characterized in that: include: Chip IC1 is used to detect the input voltage and send out a driving signal; Clamping diode D2, connected to the output of IC1; An undervoltage detection circuit includes resistors R3 and R5; An overvoltage detection circuit, including resistors R2 and R4; Input surge protection diode D1; Input current detection resistor R1; Two MOS tubes Q1 and Q2 that form switches; Power setting resistor R6; Charging time setting resistor C3.

2. The multifunctional input surge suppression circuit according to claim 1, characterized in that: IC1 sends a driving signal when the input voltage meets the conditions, detects the input current through R1, and drives Q1 and Q2 according to the preset starting power.

3. The multifunctional input surge suppression circuit according to claim 1 or 2, characterized in that: When the input is overvoltage, IC1 can detect and prevent Q1 and Q2 from conducting.

4. The multifunctional input surge suppression circuit according to claim 1 or 2, characterized in that: When the input terminal is reversed, IC1 does not work, causing Q1 and Q2 to be non-conductive.

5. The multifunctional input surge suppression circuit according to claim 1, characterized in that: When the subsequent switching power supply device is short-circuited, IC1 can collect the abnormal current and pull down the Q1 and Q2 signals to prevent damage.

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