Output circuit for interfacing integrated circuits having different power supply potentials
US5396128A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1993 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Sep 13, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/0018
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output driver circuit has a circuitry portion (70) which is used to generate a Drive-Hi control signal in response to an Output Enable, an optional Precondition signal, and a Data Input signal. A circuit portion (75) ensures that the Drive-Hi control signal is maintained at a voltage which is substantially equal to Vdd when the Output Enable is deactivated. Circuit portion (80) selectively controls the Data Output by driving Vdd onto the Data Output in response to the Drive-Hi control signal being activated. A circuit portion (100) functions to selectively drive the Data Output to a logic zero (ground potential) when a Drive-Lo signal is asserted. Circuit portions (90 and 95) generate the Drive-Lo signal in response to the Output Enable, the optional Precondition signal, and the Data Input signal. In general, the output driver circuit allows an integrated circuit powered at a first voltage to interface to another integrated circuit which is powered at a higher second voltage without loss of performance, without excessive leakage currents, without crossover current, and without increasing gate oxide stresses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.