半导体学报2011，Vol.32Issue(9)：82-88,7.DOI:10.1088/1674-4926/32/9/095002
A low power 8th order elliptic low-pass filter for a CMMB tuner
A low power 8th order elliptic low-pass filter for a CMMB tuner
摘要
Abstract
This paper presents an 8th order active-RC elliptic low-pass filter (LPF) for a direct conversion China Mobile Multimedia Broadcasting (CMMB) tuner with a 1 or 4 MHz -3 dB cutoff frequency (f-3dB).By using a novel gain-bandwidth-product (GBW) extension technique in designing the operational amplifiers (op-amps),the proposed filter achieves 71 dB stop-band rejection at 1.7f-3dB to meet the stringent CMMB adjacent channel rejection (ACR) specifications while dissipates only 2.8 mA/charmel from a 3 V supply,its bias current can be further lowered to 2 mA/channel with only 0.5 dB peaking measured at the filter's pass-band edge.Elaborated common-mode (CM) control circuits are applied to the filter op-amp to increase its common-mode rejection ratio (CM RR) and effectively reject the large signal common-mode interference.Measurement results show that the filter has 128 dBμVrms in-band IIP3 and more than 80 dB passband CMRR.Fabricated in a 0.35-μm SiGe BiCMOS process,the proposed filter occupies a 1.19 mm2 die area.关键词
CMMB tuner IC/ continuous-time filter/ active-RC filter/ low power analog filter/ gain-bandwidth-product extension/ CMRRKey words
CMMB tuner IC/ continuous-time filter/ active-RC filter/ low power analog filter/ gain-bandwidth-product extension/ CMRR引用本文复制引用
Gong Zheng,Chen Bei,Hu Xueqing,Shi Yin,Dai Fa Foster..A low power 8th order elliptic low-pass filter for a CMMB tuner[J].半导体学报,2011,32(9):82-88,7.基金项目
The author would like to thank He Juan,Zhou Changlei,Wu Zhaosheng and Guan Xin for their help in layout and testing. （）
