Overvoltage protection circuit

Abstract

The invention discloses an overvoltage protection circuit. The circuit includes a voltage input terminal (VIN) and a voltage output terminal (VOUT) between which a first resistor (R1) is connected in series. The circuit is characterized by further comprising a voltage regulating circuit connected in parallel with the first resistor (R1), the voltage regulating circuit comprising a first NPN bipolar triode (N1), a second NPN bipolar transistor (N2), a first PNP bipolar transistor (P1), a second PNP bipolar transistor (P2), a second resistor (R2), a third resistor (R3), a first avalanche diode or a first Zener diode (D1), and a second avalanche diode or a second Zener diode (D2). The beneficial effects of the invention lie in that the circuit is simple in structure, requires less devices and nodes and reduces costs, power consumption and the risks of bad nodes.

Description

technical field [0001] The invention relates to an overvoltage protection circuit. Background technique [0002] The voltage required by portable electronic products is generally relatively low, generally 1.5V, 2.5V, 3.3V or 5V voltage. In the circuit, due to factors such as circuit signal interference, short circuit or unstable power supply voltage, the voltage may suddenly rise. Excessive voltage will affect the performance of the circuit, and there is a risk of burning the circuit. [0003] The overvoltage protection circuit is a necessary circuit to solve the problem of overvoltage. The structure of the circuit in the prior art is relatively complicated, and there are many devices and nodes required. More devices cause higher cost and power consumption, and more nodes cause the risk of dead pixels. big. Contents of the invention [0004] The object of the present invention is to provide an overvoltage protection circuit with a simple structure and few nodes in view o...

AI Technical Summary

Problems solved by technology

In the circuit, due to factors such as circuit signal interference, short circuit or unstable power supply voltage, it may cause a sudden increase in voltage. Excessive voltage will affect the performance of the circuit, and there is a risk of burning the circuit

[0003] The overvoltage protection circuit is a necessary circuit to solve the problem of overvoltage. The structure of the circuit in the prior art is relatively complicated, and there are many devices and nodes required. More devices cause higher cost and power consumption, and more nodes cause the risk of dead pixels. Big

Images