Time-interleaved switched-capacitor filter for reconfigurable triple-band delta-sigma converter

A time-interleaved switched-capactior filter design for a reconfigurable triple-band delta-sigma (ΔΣ) analog-to-digital converter (ADC) is discussed. The proposed filter design utilizes time multiplexing of sampled data to capacitors, and it is useful in implementing a dual-band (low-pass and high-pass) delta-sigma converter, or a single-band band-pass delta-sigma converter. Either of these two configurations can be selected in real time by changing clock signals and output downsampling filters. The basic reconfigurable triple-band filter can be applied directly to many higher-order delta-sigma architectures. Behavioral simulations of first-order and second-order time-multiplexed dual-band (low-pass and high-pass) converters, and second-order and fourth-order band-pass converters are presented. The proposed triple-band filter is useful for the implementation of a sensor micro system-on-a-chip with communication capability.