The ADL5330 is a high performance, voltage-controlled variable gain amplifier/attenuator for use in applications with frequencies up to 3 GHz. The balanced structure of the signal path minimizes distortion while it also reduces the risk of spurious feed-forward at low gains and high frequencies caused by parasitic coupling. While operation between a balanced source and load is recommended, a single-sided input is internally converted to differential form.
The input impedance is 50 Ω from INHI to INLO. The outputs are usually coupled into a 50 Ω grounded load via a 1:1 balun. A single supply of 4.75 V to 5.25 V is required.
The 50 Ω input system converts the applied voltage to a pair of differential currents with high linearity and good common rejection even when driven by a single-sided source. The signal currents are then applied to a proprietary voltage-controlled attenuator providing precise definition of the overall gain under the control of the linear-in-dB interface. The GAIN pin accepts a voltage from 0 V at minimum gain to 1.4 V at full gain with a 20 mV/dB scaling factor.