A Low Power Mobile TV Tuner Baseband for CMMB Application

摘要

A Mobile TV tuner baseband for the newly established China Mobile Multimedia Broadcasting (CMMB) is presented. The baseband VGA achieves more than 40dB gain tuning with temperature compensation. The baseband filter provides 0.5dB passband ripple and -35dB attenuation at 6MHz with the cutoff frequency at 4MHz. In addition,the calibration of filter is reported to achieve the bandwidth accuracy of 3%. A DC offset cancellation circuit is also introduced to remove the offset from layout and self-mixing,and the remaining offset voltage and current consumption are only 6mV and 412uA respectively. Implemented in a 0.35um SiGe technology with 1.1mm2 die size,this tuner baseband achieves OIP3 of 25.5dBm and consumes 16.4mA under 2.8-V supply.