Discrete-time charge-domain filter with charge buffer for flexible design of FIR filter

A discrete-time charge-domain filter (CDF) with wide bandwidth and high attenuation is proposed. By employing a charge buffer with timing control to move a sampled charge between capacitors, the CDF can reduce the number of pulses and select a decimation rate effectively. Measurement showed 13 MHz bandwidth and 88.86 dB attenuation in a 90 nm CMOS process.