AD603 is a low noise, voltage-controlled amplifier from ADI that provides accurate, pin selectable gains of -11 dB to +31 dB with a bandwidth of 90 MHz or +9 dB to +51 dB with a bandwidth of 9 MHz. Any intermediate gain range may be arranged using one external resistor. The input referred noise spectral density is only 1.3 nV/√Hz and power consumption is 125 mW at the recommended ±5 V supplies.