A Low Power Base-Band Circuit for Low-IF Wireless PAN Receivers

A fully integrated CMOS base-band part of a low-IF WPAN receiver is presented, which consists of an active complex filter, an automatic gain control unit, and a 10-Bit Pipe-Line ADC. The highlights of the receiver include a low- power active complex filter with a nonconventional Gm-C structure and a high-resolution, low power pipe line ADC using averaging and double sampling techniques. The chip was designed on a small die using 0.18-um standard CMOS process. The filter provides more than 55 db image rejection ratio and IM3 of -50 dB for 1.9 & 2.1 MHz signals with 0.2Vpp. The converter has a peak SFDR of 61 dB, maximum DNL of 0.5 LSB, and INL of 0.9 LSB. The all parts of the scheme consume an active current about 4mA from a 1.8-V power supply.