AD603

Data Sheet Low Noise, 90 MHz Variable Gain Amplifier AD603 FEATURES Linear-in-dB gain control Pin-programmable gain ranges −11 dB to +31 dB with 90 MHz bandwidth 9 dB to 51 dB with 9 MHz bandwidth Any intermediate range, for example −1 dB to +41 dB with 30 MHz bandwidth Bandwidth independent of variable gain 1.3 nV/√Hz input noise spectral density ±0.5 dB typical gain accuracy The decibel gain is linear in dB, accurately calibrated, and stable over temperature and supply. The gain is controlled at a high impedance (50 MΩ), low bias (200 nA) differential input; the scaling is 25 mV/dB, requiring a gain control voltage of only 1 V to span the central 40 dB of the gain range. An overrange and underrange of 1 dB is provided whatever the selected range. The gain control response time is less than 1 μs for a 40 dB change. The differential gain control interface allows the use of either differential or single-ended positive or negative control voltages. Several of these amplifiers...