Patent · US Active

I/O protection under over-voltage and back-drive conditions by single well charging

US7605619B1 · kind B1 · utility

1Cited by

5References

12Claims

0Family size

Assignee

NATIONAL SEMICONDUCTOR CORPORATION · US

Inventors

Weiye Lu · Sunnyvale, US
Elroy M. Lucero · San Jose, US
Khusrow Kiani · Oakland, US

Key dates

Filing date	Mar 21, 2007
Grant date	Oct 20, 2009
Priority date	—
Expiry date	Mar 21, 2027

Classification

Technology area (CPC H)Electricity
CPC primaryH03K2217/0018
WIPO fieldBasic communication processes
WIPO sectorElectrical engineering

Abstract

In an I/O driver that includes a cascoded pair of PMOS driver transistors connected to a pair of cascaded NMOS driver transistors and that defines a pad output between the PMOS and NMOS driver transistors, a method of providing the CMOS I/O driver with over-voltage and back-drive protection includes providing circuitry for charging the wells of the PMOS transistors either to VDDIO during normal voltage mode by making use of the power supply, or to a common voltage during over-voltage and back-drive operation using the pad voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.