This paper describes a VLSI implementation of the InfoMax algorithm for Independent Component Analysis in mixed-signal CMOS. Our design uses on-chip calibration techniques and local adaptation to compensate for the effect of device mismatch in the arithmetic modules and analog memory cells. We use our design to perform two-input blind source-separation on mixtures of audio signals, and on mixtures of EEG signals. Our hardware version of the algorithm successfully separates the signals with a resolution within less than 10% of a software implementation of the algorithm. The die area of the circuit is 0.016mm(2) and its power consumption is 15 mu W in a 0.35 mu m CMOS process.