Reconfigurable High-Order Moving-Average Filter Using Inverter-Based Variable Transconductance Amplifiers

A charge sampler-based reconfigurable high-order moving-average (MA) filter designed using a temporal MA method is proposed. The proposed filter has a higher gain than conventional MA filters. Moreover, the filter supports variable sizes and orders of MA. That is, the filter has a flexible frequency response by changing not only the sampling frequency but also the MA size (N) and MA order (M). The N and M are easily controlled by changing the clock patterns; therefore, the filter is suitable for multimode transceivers. To minimize the power consumption, inverter-based transconductance amplifiers are used. Here, our fabricated filter using a 65-nm CMOS technology supports MA (N = 2, M = 3) and MA (N = 3, M = 2) without changing the hardware.