PXI-5690 Block Diagram

Channel 0 (CH 0) functions as a fixed gain amplifier. Channel 1 (CH 1) functions as a programmable amplifier containing two user-selectable paths.

Channel 0

This channel offers low noise figure and a flat frequency response. Use CH 0 as you would a conventional fixed gain amplifier.

Channel 1 User-Selected Paths

The main path consists of fixed gain amplification preceded by a step attenuator that is adjustable in 1 dB nominal steps according to user-specified gain settings. By default, CH 1 is initialized to use the main path with maximum gain.

The direct path provides the option of bypassing the attenuator-amplifier circuitry. This path is useful for handling higher power inputs that may cause distortion in the RF amplifier.