Static discharging protection circuit

Abstract

A static discharging protection circuit comprises an emitter connected with an external circuit, a collector is grounded with a PNP tube by a first parasitic resistor; the collector is connected with the external circuit by a second parasitic resistor; the emitter is grounded with an NPN tube; a trigger voltage regulating circuit is connected with the base electrode of the PNP tube and the base electrode of the NPN tube, and the trigger voltage regulating circuit comprises a diode string. The trigger voltage of the static discharging circuit has high regulating freedom degree, and the processis low in cost.

Description

technical field [0001] The invention relates to an electrostatic discharge protection circuit. Background technique [0002] Nowadays, with the improvement of integrated circuit manufacturing process, the feature size of CMOS integrated circuits is getting smaller and smaller. However, along with it, the protection ability of integrated circuits against electrostatic discharge (ESD, Electrostatic Discharge) is getting weaker and weaker, that is, as the size of devices becomes smaller and smaller, the electrostatic voltage that devices can withstand is also getting smaller and smaller. . Moreover, since the static electricity in the working environment of the integrated circuit will not change due to the reduction of the size of the integrated circuit, compared with the large-scale integrated circuit, the integrated circuit manufactured by the deep submicron manufacturing process is easier to Damaged by electrostatic discharge. [0003] It is usually the input / output circu...

AI Technical Summary

Problems solved by technology

[0006] The problem solved by the present invention is the low degree of freedom in adjusting the trigger voltage of the silicon controlled rectifier structure in the prior art

Images