AD603ARZ 特殊用途放大器

AD603ARZ

特殊用途放大器 IC Low Noise, 90 MHz  Variable Gain Amplifier

FEATURES AD603ARZ

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

APPLICATIONS AD603ARZ

RF/IF AGC amplifiers

Video gain controls

A/D range extensions

Signal measurements 

GENERAL DESCRIPTION AD603ARZ

The AD603 is a low noise, voltage-controlled amplifier for use

in RF and IF AGC systems. It 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. 

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.