Feedback-controlled current output driver having reduced current surge
US4825099A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 4, 1987 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Dec 4, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/6872
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output pad driver circuit for an integrated circuit chip architecture incorporates a controllably switched current mirror circuit in the circuit path between an output pad driver input terminal to which a digital signal produced by the signal processing circuitry of the chip is applied and an output terminal from which an output signal produced by the output pad is produced. The controllably switched current mirror circuit is coupled to a reference current terminal to which a source of reference current is applied. Coupled between the input terminal and the current mirror circuit is a first switching transistor which controllably causes the controllably switched current mirror circuit to apply a controlled current to the output terminal in response to a prescribed change in the logic level of an input signal that is applied to the input terminal. A second switching transistor is coupled in a feedback path between the output terminal and the current mirror circuit, and causes the current mirror circuit to terminate the supply of controlled current to the output terminal in response to the voltage level at said output terminal reaching a prescribed threshold. A third switching tra…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.