A 3rd-order current-mode continuous-time filter in 65 nm CMOS

A 3
^rd
-order continuous-time current-mode filter in 65 nm CMOS technology with a switchable cut-off frequency between 1.1 MHz and 4.4 MHz for software defined radio on chip is presented. An innovative extension to a structure in literature is proposed, that allows to save chip area at low cut-off frequencies. The realized chip has an active area of 0.077 mm
²
and consumes 12.3 mW at 1.2 V. The dynamic range for a bandwidth of 1.1 MHz is 77.2 dB, the in-band current noise is 31.16 pA/radicHz and the IIP3 is 1.8 mA
_p
.