Gain control circuit, and a radio communication apparatus using the same

摘要

A gain control circuit comprises a variable gain circuit having a predetermined gain control range and a control voltage supply circuit for supplying an internal control voltage to the variable gain circuit as a gain control signal. In this gain control circuit, the control voltage supply circuit generates the internal control voltage in response to an external control voltage so as to compensate the linearity of the variable gain circuit to the extent of the external control voltage where the variable gain circuit loses linearity. This gain control circuit is applied to an AGC circuit of the transmitting stage in a CDMA-type mobile phone.