A low power monolithic AGC with automatic DC offset cancellation for direct conversion hybrid CDMA transceiver used in telemetering
Hung Yan Cheung, King Sau Cheung, Jack Lau · 2000
The monolithic integration can be made possible with the advantages of direct conversion techniques. However, DC offset and flicker noise become critical to the system. In this paper we propose a wide tuning range AGC with an effective automatic DC offset cancellation. The proposed AGC is specifically designed for direct conversion hybrid CDMA system operating at 2.4 GHz used in telemetering applications. The AGC was fabricated using TSMC 0.35 um double poly process. The circuit achieves a 80 dB continuous gain tuning range, [-30 dB, 50 dB], with 40 dB dynamic range for differential output voltage set to 500 mV/sub pp/ and a THD better than 30 dBc. The AGC is powered by 3 V with 7 mW power consumption.