Low di/dt BiCMOS output buffer with improved speed
US5140191A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1990 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Nov 5, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/00346
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output buffer for a device such as a memory comprises a voltage regulator, a current source portion, a switching portion, and an output portion. The voltage regulator provides a constant voltage independent of fluctuations between first and second power supply voltages. The current source portion provides first and second currents to first and second nodes to limit the rate at which transistors in the output portion become conductive. The switching portion provides voltage signals on the first and second nodes respectively in response to positive and negative voltage differences between first and second input voltages. The output portion provides an output signal at either a logic high or a logic low voltage respectively in resonse to the voltage signals at the first and second nodes. The current source portion allows the use of faster bipolar transistors to improve the speed of the output buffer while maintaining accepable di/dt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.