Output pad precharge circuit for semiconductor devices
US6281719A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1999 |
| Grant date | Aug 28, 2001 |
| Priority date | — |
| Expiry date | Oct 29, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/00315
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output driver for an integrated circuit performs a precharge function before internal data is available, minimizing the access time for such data. Also, the pull up and pull down circuitry used in the precharge function is separate from the output driver, and independent of the level of the data signal to be driven. A sense circuit senses an initial state of the output pad, before the output signal is supplied to the output pad, which indicates whether a voltage level on the output pad is above a threshold or below the threshold. A precharge circuit includes a pull up circuit and a pull down circuit. The pull up circuit is responsive to the initial state indicating that the voltage level on the output is below the threshold, and the pull down circuit is responsive to the initial state indicating that the voltage level on the output is above the threshold. A detector is coupled to the output, and produces a control signal indicating when output is near the threshold. Logic is responsive to the control signal from the detector to turn off the precharge circuit when the threshold is reached.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.