A buffer circuit is arranged for offset cancellation between an input voltage and a buffered voltage. The buffer circuit includes two bias current sources, two p-type transistors, and two n-type transistors. Further, the base-emitter voltages of the two p-type transistors and the two n-type transistors are arranged to form a translinear loop. The translinear loop is arranged to provide the buffered voltage from the input voltage. One of the bias sources is arranged to provide a bias current to one of the p-type transistors, and the other bias circuit is arranged to provide a bias current to one of the n-type transistors. One of the bias current circuits is arranged to actively sense the reverse saturation currents of the p-type transistors and the n-type transistors, and to provide its bias current so that the offset voltage between the input voltage and the buffered voltage is substantially cancelled.