Emitter follower circuit with MOSFET
US4958094A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1989 |
| Grant date | Sep 18, 1990 |
| Priority date | — |
| Expiry date | Jun 28, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/0016
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In an emitter follower circuit including an emitter follower transistor (Q3, Q4), and a series-connected circuit connected to the emitter of the emitter follower transistor and including a current source (Q3, Q4) and a current source resistor, the current source resistor being formed by a MOS transistor (N4, N5), the emitter follower circuit being switched to active and inactive states by switching the state of the MOS transistor (N4, N5) by a control signal, there is provided current path means provided between the source and drain of the MOS transistor, for providing a resistance considerably larger than a resistance of the MOS transistor provided during conducting when the MOS transistor is at least cut off and passing an extremely small current passes therethrough at that time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.