Slew rate controlling method and system for output data
US6958638B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 2003 |
| Grant date | Oct 25, 2005 |
| Priority date | — |
| Expiry date | Oct 9, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/00384
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A slew rate controlling system for output data is provided which is capable of improving an output data window even when change in a potential difference between a first power supply (VDD) to be used for outputting and a second power supply (VDDQ) to be used internally occurs. The slew rate controlling system is achieved by using a VDD-VDDQ potential difference detecting circuit to detect a decrease in a potential difference between the first power supply (VDD) and the second power supply (VDDQ) and to produce a first signal with specified timing and to detect an increase in a potential difference between the first power supply (VDD) and the second power supply (VDDQ) and to produce a second signal and by using a slew rate controlling circuit to exert control, when the first signal is significant, to enlarge a transition speed in a fall of output data and to exert control, when the second signal is significant, to enlarge the transition speed in a rise of output data and to produce output data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.