A 4th-order low-pass filter (LPF) based on active-Gm-RC structure for multi-standard system application is presented in this paper. The performances of LPF are controlled by a 1-bit control- voltage, and the cut-off...A 4th-order low-pass filter (LPF) based on active-Gm-RC structure for multi-standard system application is presented in this paper. The performances of LPF are controlled by a 1-bit control- voltage, and the cut-off frequency, channel selectivity, and linearity of the proposed filter can be reconfigured accordingly. In order to improve the accuracy of the cut-off frequency, a binary-weigh- ted switched-capacitor array is employed as the auto-tuning circuits to calibrate the RC-time con- stant. Fabricated in TSMC 0. 18μm RF CMOS process, the proposed LPF achieves a measured cutoff frequency of 1.95 and 12.3MHz for WCDMA and GPS/Galileo application with a bandwidth de viation less than 4%. The measured l dB compression points are -3.0dBm and -5.1 dBm respectively for different modes. The core circuit of LPF consumes l mW and 1.6mW for WCDMA and GPS/Galileo respectively. And the proposed LPF occupies an area of 0.78ram2.展开更多
基金Supported by the National Basic Research Program of China(No.2010CB327404)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A 4th-order low-pass filter (LPF) based on active-Gm-RC structure for multi-standard system application is presented in this paper. The performances of LPF are controlled by a 1-bit control- voltage, and the cut-off frequency, channel selectivity, and linearity of the proposed filter can be reconfigured accordingly. In order to improve the accuracy of the cut-off frequency, a binary-weigh- ted switched-capacitor array is employed as the auto-tuning circuits to calibrate the RC-time con- stant. Fabricated in TSMC 0. 18μm RF CMOS process, the proposed LPF achieves a measured cutoff frequency of 1.95 and 12.3MHz for WCDMA and GPS/Galileo application with a bandwidth de viation less than 4%. The measured l dB compression points are -3.0dBm and -5.1 dBm respectively for different modes. The core circuit of LPF consumes l mW and 1.6mW for WCDMA and GPS/Galileo respectively. And the proposed LPF occupies an area of 0.78ram2.