A rail-to-rail ping-pong op-amp achieves offset cancellation and 1/f n
oise reduction without folding of the input spectrum, The clocking sch
eme minimizes the clock feedthrough and the residual offset due to cha
rge injection, With a clock frequency of 100 KHz, the residual offset
is less than 100 mu V, and the input referred noise is about 225 nV/Hz
(1/2). The rail-to-rail distortion at 1 kHz is lower than -71 dB, The
total silicon area is 610 x 420 mu m(2), and tile circuit dissipates 1
.5 mW from a single 5 V supply.