Low switching noise output buffer
US5420525A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1993 |
| Grant date | May 30, 1995 |
| Priority date | — |
| Expiry date | Jun 28, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/00361
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The switching noise generated by a data output buffer is greatly reduced by "precharging" the output node to an intermediate voltage during a system's "dead" time. This is done with a precharging output current pulse having a constant time derivative during a first time interval and a constant time derivative of opposite sign during a second time interval, before performing the actual switching with an output current having a constant time derivative, during a third time interval. The partial precharging with a controlled, triangular-shaped, output current pulse, avoids any abrupt change of output current and thus limits switching noise. The buffer of the invention is particularly useful in high-speed memory devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.