Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Electro Static Discharge Protect Circuit

IP.com Disclosure Number: IPCOM000118566D
Original Publication Date: 1997-Mar-01
Included in the Prior Art Database: 2005-Apr-01
Document File: 4 page(s) / 51K

Publishing Venue

IBM

Related People

Onishi, S: AUTHOR

Abstract

Disclosed is an Electro Static Discharge (ESD) protect circuit, where its ground is not connected to the substrate. This design achieves the similar ESD robustness to the normal ESD protect circuit. It becomes available without any area penalty by modifying metal wiring of the normal ESD protect circuit.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Electro Static Discharge Protect Circuit

      Disclosed is an Electro Static Discharge (ESD) protect circuit,
where its ground is not connected to the substrate.  This design
achieves the similar ESD robustness to the normal ESD protect
circuit.  It becomes available without any area penalty by modifying
metal wiring of the normal ESD protect circuit.

      Fig. 1 shows the wiring of the normal ESD protect circuit.  In
this case, the circuit diminishes the ESD voltage to a harmless level
effectively through two discharge paths, to VCC and from grounded
substrate, as shown in Fig. 3.

      Fig. 2 shows the wiring of the new ESD protect circuit design
method.  In this case, there are two types of Grounds, as shown in
Fig. 4.  One is connected to the substrate and the other one is not
connected to the substrate (1).  The new scheme keeps the same
structure as Fig. 3 for the part of the circuit where the ground is
connected to the substrate.  It also creates a discharge path by
adding a diode (2) for the circuit where its ground is not connected
to the substrate.

      This new design can keep the design modification time and cost
to a minimum by using the same device structure as the normal ESD
protect circuit.   Because the modification from the normal ESD
protect circuit is only metal wiring change, no additional circuit
area is required.