Signal strength detector
AssigneePlessey Overseas Limited
InventorPhilip A. K. Moon
Life of this patent
Estimating the term…
Abstract
A signal strength detector comprises first, second and third transistors of the same conductivity type. The emitter electrodes of each transistor are connected together and coupled with one of a pair of dc supply lines. The collector electrodes of the first and second transistors are each coupled with the other of the pair of dc supply lines. The base electrode of the first and second transistors are each coupled via a resistor to the base electrode of the third transistor. The collector electrode of the third transistor is effective to provide a source of output current which is representative of a differential signal level between the base electrodes of the first and second transistors.
Claims16
A signal strength detector, comprising:
- first, second and third transistors of the same conductivity type, each having an emitter electrode, a collector electrode and a base electrode;
- a pair of dc supply lines, the emitter electrode of each transistor being connected together and coupled to one of the pair of dc supply lines via a constant current source, and the collector electrodes of the first and second transistors each being coupled with the other of the pair of dc supply lines;
- a first resistor through which the base electrode of the first transistor is coupled to the base electrode of the third transistor;
- and a second resistor through which the base electrode of the second transistor is coupled to the base electrode of the third transistor, wherein the collector electrode of the third transistor is effective to provide a source of output current which is representative of a differential signal level between the base electrodes of the first and second transistors.
Dependencies are inferred from the claim text.