On-chip self-calibration system for CMOS active inductor band pass filter

A calibration system aiming for automatically correcting the effect of process variation on performance of on-chip Active Inductor Band Pass Filter (AIBPF) is presented. The benefit of using active inductors to build on-chip band pass filter is less chip area consumption and the tunability of center frequency compared to designs employing passive inductors. However, the fatal drawback of active inductor is performance degradation caused by process variation generated during chip fabrication. The proposed calibration system has the ability to detect process variation and adjust the AIBPF center frequency back to the designed 5.2 GHz by compensating the bias voltage. Simulation results show this calibration system can significantly improve the yield of circuits employing AIBPFs.