Signal processing semiconductor integrated circuit device and wireless communication system

摘要

Disclosed herein is a direct conversion type signal processing semiconductor integrated circuit device capable of suppressing a DC voltage variation in the output of a variable gain amplifier upon the transition to a reception mode, reproducing stable receiving characteristics and improving receiving sensitivity. In the signal processing semiconductor integrated circuit device, voltage reference circuits for generating reference voltages for controlling or restricting currents for current sources for supplying operating currents for amplifiers constituting a reception-system circuit are boosted upon the transition from an idle mode or the like to the reception mode to allow the currents to flow into the constant-current sources of the amplifiers after the stabilization of the generated reference voltages.