Transient controlled current switch
US4409498A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1980 |
| Grant date | Oct 11, 1983 |
| Priority date | — |
| Expiry date | Dec 30, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/0136
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A current controlled gate performing a NOR function utilizes a pair of transistors acting as current mirrors that receive a DC bias through a large resistor. This bias occurs when an input transistor is positive to insure that one of the current mirror transistors will saturate when the input transistors are "off" and the other will be driven into saturation when either of the input transistors is "on". When all inputs are negative, one of the current mirror transistors saturates thereby reducing the current to the input transistors effectively to zero. The saturation results in the collector-base capacitance increasing very rapidly such that the input assumes the characteristics of a common emitter due to the large capacitance existing in the collector of the current mirror transistor. An active push-pull output is produced with a single collector path from input to output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.