Signal amplifying circuit
US4021749A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1975 |
| Grant date | May 3, 1977 |
| Priority date | — |
| Expiry date | Feb 6, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G1/0023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A signal amplifying circuit including an amplifying transistor having its base-emitter terminals connected to a signal source. A diode having the proper characteristics is also connected across the base-emitter input terminals to produce a first reference bias voltage to be applied to the input circuit of the transistor. The emitter-collector circuit of a compensating transistor is connected in series with the emitter-collector circuit of the amplifying transistor, and a second reference bias voltage is connected between the base of the compensating transistor and the emitter of the amplifying transistor. The second reference bias voltage is produced across a plurality of diodes having the proper characteristics, whereby the current gain of the amplifier will be constant regardless of variations in the transistor characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.