ADJUSTMENT OF BIAS CURRENT IN A FIRST INTEGRATED CIRCUIT BASED ON A SIGNAL GAIN OF A SECOND INTEGRATED CIRCUIT

摘要

A technique of adjusting the bias current of an active circuit in a transmit signal path based on the signal gain(s) of variable gain element(s) located prior to the active circuit. The technique is particularly advantageous when the gain element(s) are located on one IC (e.g., that implements an IF portion) and the active circuit is implemented on another IC (e.g., that implements a RF portion). The bias current of the active circuit is set based, in part, on the input power level, which may be inferred from the gain control signal(s) used to control the preceding variable gain elements. Initially, at least one gain control signal. A bias current for the active circuit is then determined based, in part, on the estimated input signal level. The active circuit is biased with the determined bias current. The biased current can be limited to a range defined by an upper bias current and a lower bias current.