Abstract
There is a current trend in monolithic integration for wireless transceivers. This technique is wildly used in the 3G communications system. In this paper, it was proposed to design a high dynamic range AGC with an automatic DC offset cancellation. The AGC is designed for the direct conversion WCDMA system operating at 2.4GHz. The circuits are fabricated using TSMC 0.35um SiGe BiCMOS process. The performance of the AGC will not be affected by the DC offset effects, and the high dynamic range is increased by the large gain tuning range. As the simulation results, the circuit achieves a 107dB continuous gain tuning range, [-27dB, 80dB], with 69dB dynamic range for differential output voltage set to 1Vpp and a THD better than 30dBc. The AGC’s core circuits are powered by 3.3V with 1.6mW power consumption. Finally, it has discussed with comparing the simulation and measurement results.