This part is used in the MFOS Sonic Multiplier and the ULTIMATE EXPANDER. The AD633 is a functionally complete, four-quadrant, analog multiplier. It includes high impedance, differential X and Y inputs and a high impedance summing input (Z). The low impedance output voltage is a nominal 10 V full scale provided by a buried Zener.

See the AD633AN data sheet for complete specs.