Output buffer circuit with signal feed forward for reducing switching induced noise
US5081374A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1990 |
| Grant date | Jan 14, 1992 |
| Priority date | — |
| Expiry date | Feb 22, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/00361
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output buffer circuit reduces switching induced noise in integrated circuit devices. A pulldown feed forward circuit is coupled between the input and the output pulldown transistor. The pulldown feed forward circuit bypasses at least some of the intermediate circuit elements of the output buffer circuit. The pulldown feed forward circuit initiates a relatively small sinking current through the output pulldown transistor in response to a first signal at the input before the intermediate circuit elements initiate relatively large sinking current through the output pulldown transistor means. A pullup feed forward circuit is coupled between the input and the output pullup transistor means. The pullup feed forward circuit bypasses at least some of the intermediate circuit elements of the output buffer circuit. The pullup feed forward circuit initiates a relatively small sourcing current through the output pullup transistor means in response to a second signal at the input before the intermediate circuit elements initiate the relatively large sinking current through the output pullup transistor. The output pulldown may include a relatively large current carrying capacity primary pulld…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.