零中频DVB-H调谐器中信道选择滤波器的设计  

Design of Channel-Select Filter for ZIF DVB-H Tuner

作　　者：戚建烨[1] 王小力[1] 王守军 

机构地区：[1]西安交通大学VLSI技术研究中心,西安710049 [2]IDT科技(上海)有限公司,上海200233

出　　处：《微电子学》2008年第2期289-293,共5页Microelectronics

基　　金：教育部科学技术基金重点资助项目(03151)

摘　　要：介绍了零中频结构DVB-H调谐器中信道选择滤波器及其自动频率校准电路的设计。该滤波器采用7阶切比雪夫(Chebyshev)I型低通结构,截止频率3/3.5/4 MHz可编程;在偏离截止频率1.25/4 MHz的频点上,分别实现24/56 dB衰减。为了补偿RC常数漂移,设计了一个基于逐渐近似(SAR)算法的自动频率校准电路,在N比特精度下,仅需要N个时钟周期就能完成校准。相比传统技术,明显提高了校准速度。基于TSMC 90 nm数字CMOS工艺,在1.2 V电源电压下进行了仿真实验。结果表明,滤波器的输入等效噪声为48 nV/Hz,三阶交调点(IIP3)达到26 dBm,频率校准精度在2.5%以内,功耗为16 mW。A channel-select filter with an automatic tuning circuit for ZIF （zero intermediate frequency） DVB-H tuner was designed. The filter topology was the 7^th-order Chebyshev I low pass type, and the programmable band- width was 3/3.5/4 MHz with an attenuation of 24/56 dB at offsets of 1. 25/4 MHz. A successive approximation register （SAR） scheme was incorporated in the onhip tuning circuit to speed up the tuning time, which is proportional to the number of bits of resolution. By using this tuning technique, less than 2.5% cut-off frequency error was obtained. The simulated equivalent input referred noise （IRN） was 48 nV/v√z and the third-order intercept point （IIP3） was 26 dBm. Designed in TSMC＇s 90 nm digital CMOS process, the fiker dissipates only 16 mW of power for a supply voltage of 1.2 V.

关 键 词：零中频 数字视频广播 低通滤波器 Tow-Thomas滤波器 自动频率校准 

分 类 号：TN713.4[电子电信—电路与系统]