The AD834 is a monolithic laser-trimmed four-quadrant analogmultiplier intended for use in high frequency applications, hav-ing a transconductance bandwidth (RL= 50？)in excess of500 MHz from either of the differential voltage inputs. In multi-plier modes, the typical total full-scale error is 0.5%, dependenton the application mode and the external circuitry. Performanceis relatively insensitive to temperature and supply variations, dueto the use of stable biasing based on a bandgap reference genera-tor and other design features.To preserve the full bandwidth potential of the high speedbipolar process used to fabricate the AD834, the outputs appearas a differential pair of currents at open collectors. To provide asingle ended ground referenced voltage output, some form of ex-ternal current to voltage conversion is needed. This may take theform of a wideband transformer, balun, or active circuitry suchas an op amp. In some applications (such as power measure-ment) the subsequent signal processing may not need to havehigh bandwidth.