A 1-V 3.5-mW CMOS switched-opamp quadrature IF circuitry for Bluetooth receivers

Based on only half-delay switched-capacitor integrators, a 7/sup th/-order IF-filter and a 3/sup rd/-order /spl Sigma//spl Delta/ modulator using a novel noise-shaping extension technique are implemented for a Bluetooth receiver in a 0.35-/spl mu/m CMOS process. At a 1-V supply, the quadrature IF circuitry achieves a measured IIP3 of -3 dBm at a nominal gain of 24 dB through a 48-dB variable-gain control with a power dissipation of 3.5 mW.