一种0.13 μm CMOS多模信道选择滤波器的设计

Design of 0.13 μm CMOS Multi-Mode Channel Selection Filter

设计了一款应用于多模多频无线接收机中的新型有源电阻电容信道选择滤波器,截止频率可在0.3～10MHz之间切换,满足UHF RFID、TD-SCDMA、WLAN a/b/g等不同标准的要求。运算放大器设计采用无电容前馈补偿技术,增益带宽积提升至4.8GHz。滤波器采用5阶Leapfrog滤波器级联2阶Tow-Thomas滤波器结构,使截止频率不易受器件变化的影响,同时兼顾稳定性和可调性。电路采用IBM 0.13μm CMOS工艺流片。测试结果表明,在2.5V电源电压下选择10MHz带宽时,滤波器消耗13.56mA电流,在两倍截止频率处实现64dB的衰减,带内噪声系数为28dB,带内纹波小于0.2dB,带内输入3阶交调为11.5dBm。

A novel active-RC analog baseband channel selection filter for multi-mode/multi-frequency wireless receiver was presented,of which the cut-off frequency was variable from 0.3 MHz to 10 MHz to satisfy UHF RFID,TD-SCDMA,and WLAN a/b/g standards.No-capacitor feed-forward compensation was adopted in operational amplifier design,which improved its GBW up to 4.8 GHz.A 5th-order leapfrog filter was cascaded with a 2nd-order Tow-Thomas filter,which reduced cut-off frequency variation and also guaranteed stability and reconfiguration of the device.This design was implemented in IBM 0.13 μm CMOS process.Test results showed that the filter could provide 64 dB attenuation at double cut-off frequency,while drawing 13.56 mA of current from 2.5 V power supply at 10 MHz bandwidth,and it had an input-referred noise figure of 28 dB,an in-band ripple less than 0.2 dB,and an in-band IIP3 of 11.5 dBm.