ESD PROTECTION CIRCUIT CELL

摘要

A protection cell for a cell library. The protection cell defines a protection circuit for an IC having a driving device with a first supply voltage Vdd1 and an output, and a driven device having an input and a second supply voltage Vdd2. The protection circuit includes a first device from the group consisting of a P-diode and a gate-Vdd PMOS. The first device is coupled between a first power bus connected to Vdd2 and the input of the driven device. The input of the driven device is coupled by way of a resistor to the output of the driving device. A second device corresponding to the first device is provided, from the group consisting of an N-diode and a grounded gate NMOS. The second device is coupled between the input of the driven device and a ground bus.

主权项

1. A protection circuit comprising:
a power bus; a ground bus; a first device from the group consisting of a P-diode and a gate-Vdd PMOS, the first device coupled between the power bus and an input of a driven device, the input of the driven device coupled to an output of a driving device, the first device having first and second N+ regions connected by a third N+ region with the third N+ region adjacent to the power bus; and a second device from the group consisting of an N-diode and a grounded gate NMOS, the first and second devices arranged symmetrically about horizontal and vertical centerlines of the protection circuit, the second device coupled between the input of the driven device and the ground bus.