论文信息 - 1.5 V 5.0 MHz switched capacitor circuits in 1.2 /spl mu/m CMOS without voltage bootstrapper

1.5 V 5.0 MHz switched capacitor circuits in 1.2 /spl mu/m CMOS without voltage bootstrapper

A fully-differential switched capacitor (SC) bandpass biquad and a 4/sup th/ order bandpass /spl Delta/-/spl Sigma/ modulator were designed and fabricated in 1.2 /spl mu/m CMOS process. The supply voltage is 1.5 V without using any voltage bootstrapper. The clock frequency is 5.0 MHz in both circuits. The bandpass filter had Q=8.0 and IM3=-52 dB at its central frequency of 833 KHz. The 4/sup th/ order bandpass /spl Delta/-/spl Sigma/ modulator had SNR=61 dB and IM3<-78 dB in its narrowband of 25 KHz centered at the central frequency of 1.25 MHz.

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