Patent ID: 7592794
Filing Date: 2009-09-22
Classification: H04B

Abstract:
1. A received signal strength indicator, comprising: a pair of input transistors with coupled emitters and with base electrodes to which an input signal is differentially applied; a collector load circuit associated with each input transistor, each collector load circuit including a first active device configured as a current source, connected between a first supply terminal and a collector of the respective input transistor, and including an output node; and a tail current sink including a second active device connected between a second supply terminal and the coupled emitters; wherein the first active device in each collector load circuit associated with each input transistor is adapted and configured to supply a current copied from the tail current; and wherein a signal strength indicator signal is obtained from a differential signal between the corresponding output nodes of the collector load circuits by taking the mean value of the differential signal referenced to the first supply terminal.