Design of Crosstalk Noise Filter for Multi-Channel Transimpedance Amplifier

This paper discusses design of area effective crosstalk noise reduction for multi-channel transimpedance amplifiers. For parallel integration of optical receivers, noise via the power/ground lines is a serious issue. One of the noise reduction technique is an RC filter insertion, however systematic design is still unclear. We investigate how to determine the time constant of the RC filter. Since the time constant of RC filter affects the balance of the supply noise and the ground noise, the noise reduction becomes maximum at a certain time constant. We fabricated an 180-nm CMOS test chip of parallel TIAs with the RC filter. Measurement results confirm that an adequate time constant design maximize the noise reduction and the maximum reduction ratio is 38%.