Low-voltage radio frequency amplifier
US5929708A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1997 |
| Grant date | Jul 27, 1999 |
| Priority date | — |
| Expiry date | Nov 20, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0088
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A power-conserving, linear and broad band RF amplifier, suitable for use at more than one band in the ultra-high frequency regions allotted to radiotelephone transceivers, employs an emitter-follower output transistor to deliver the nominal 1.0 milliwatt RF power to a single-ended load from a low voltage battery, typically 2.7 v. dc, without the use of output coupling transformers. The amplifier receives only a small differential input signal from the preceding mixer or multiplier stage having a typical peak-to-peak magnitude of 0.3 v. The differential input signal is applied to the emitters of a pair of transistors whose bases are interconnected, one transistor of which (B6) is diode-connected in a current-mirror configuration and the other (B5) of which is configured in a common-base connection with emitter degeneration. The signals are summed at the collector of the common-base transistor to deliver a substantial voltage swing, illustratively 1.7 volts peak to peak, which is large enough to drive the base of the emitter-follower output transistor (B3) without requiring the high standby current in the emitter-follower normally required to maintain an emitterfollower in Class A op…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.