US 2006/0220136 A1 · ELECTRO-STATIC DISCHARGE PROTECTION CIRCUIT AND SEMICONDUCTOR DEVICE HAVING THE SAME

Abstract

An electro-static discharge protection circuit comprises a thyristor mode ensuring circuit and a thyristor rectifier circuit. The thyristor mode ensuring circuit includes a capacitive element C1 connected between a higher potential line Vdd and a lower potential line Vss, and ensures a constant and sufficient capacity independently of the number of input/output signal bits, even when the number of input/output signal bits is the theoretical minimum, i.e. 1, so that a surge current induced by electro-static discharge (ESD) applied to an output pad Vout is injected into the first capacitive element C1 in order to charge it. Thus, by means of the current caused by the surge current, the thyristor rectifier circuit is triggered into a thyristor mode, which allows the surge current to flow to the lower potential line Vss through the thyristor rectifier circuit, resulting in a CMOS inverter of an internal circuitry being effectively protected against the surge current. A semiconductor device which includes the electro-static discharge protection circuit is also provided.

Claims18

Dependent claims

An electro-static discharge protection circuit, comprising:

a first thyristor rectifier circuit that is electrically coupled between first internal circuitry and a first signal input/output section to which a potential that corresponds to either an input signal to the first internal circuitry or an output signal from the first internal circuitry is to be applied, and also electrically coupled between a higher potential line and a lower potential line;
and
a first thyristor mode ensuring circuit that is electrically coupled between the higher potential line and the lower potential line, and also electrically coupled to the first thyristor rectifier circuit, in order to trigger the first thyristor rectifier circuit into a thyristor mode by means of a surge current applied to the first signal input/output section so that the surge current flows into the lower potential line through the first thyristor rectifier circuit in order to protect the first internal circuitry from the surge current.

A semiconductor device comprising:

first internal circuitry to and from which at least one bit of a digital signal is input and output;
at least one first signal input/output section which is provided for each of the at least one bits, and to which a potential that corresponds to each of the at least one bits is to be applied;
and
at least one first electro-static discharge protection circuit which is provided for each of the at least one bits and which is electrically coupled between a corresponding first input/output section of the at least one input/output section and the first internal circuitry, each of the at least one first signal input/output sections comprising:
a first thyristor rectifier circuit which is electrically coupled to the first internal circuitry and the corresponding first input/output section, and is also electrically coupled to the higher potential line and to the lower potential line;
and
a first thyristor mode ensuring circuit which is electrically coupled between the higher potential line and to the lower potential line and is also electrically coupled to the first thyristor rectifier circuit, in order to trigger the first thyristor rectifier circuit into a thyristor mode by means of a surge current applied to the first signal input/output section so that the surge current flows into the lower potential line through the first thyristor rectifier circuit in order to protect the first internal circuitry from the surge current.

4 more elements

Dependencies are inferred from the claim text.

Electro-static discharge protection circuit and semiconductor device having the same

Life of this patent

Electro-static discharge protection circuit and semiconductor device having the same

Life of this patent

Abstract

Claims18