A novel class of filters (called pipe filters) that features in-band noise reduction is presented and a current mode biquad cell based on cross-connected cascoded devices is introduced. The presented solution gives in-band high-pass noise shaping and passive pre-filtering of out-of-band blockers. This results in both low in-band noise and high out-of-band IIP3. A 4th-order low-pass prototype in 90 nm CMOS for WCDMA application features 32$ mu{hbox{V}}$ in-band noise (when integrated over the 2 MHz bandwidth as defined by the standard) and $+$ 36 dBm out-of-band IIP3 which results in a 75 dB SFDR with 1.25 mW power consumption. Active die area is 0.5 ${hbox {mm}}^{2}$.
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