GENERAL DESCRIPTION

The AD834 is a monolithic, laser-trimmed four-quadrant analog multiplier intended for use in high frequency applications, with a transconductance bandwidth (RL = 50 Ω) in excess of 500 MHz from either of the differential voltage inputs. In multiplier modes, the typical total full-scale error is 0.5, dependent on the application mode and the external circuitry. Performance is relatively insensitive to temperature and supply variations due to the use of stable biasing based on a band gap reference generator and other design features.

To preserve the full bandwidth potential of the high speed bipolar process used to fabricate the AD834, the outputs appear as a differential pair of currents at open collectors. To provide a single-ended ground referenced voltage output, some form of external current-to-voltage conversion is needed. This may take the form of a wideband transformer, balun, or active circuitry such as an op amp. In some applications (such as power measurement), the subsequent signal processing may not need to have high bandwidth.

FEATURES

DC to >500 MHz operation

Differential ±1 V full-scale inputs

Differential ±4 mA full-scale output current

Low distortion (≤0.05 for 0 dBm input)

Supply voltages from ±4 V to ±9 V

Low power (280 mW typical at VS = ±5 V)

APPLICATIONS

High speed real time computation

Wideband modulation and gain control

Signal correlation and RF power measurement

Voltage controlled filters and oscillators

Linear keyers for high resolution television

Wideband true RMS