The PXIe-5654 with PXIe-5696 has two modes for using the automatic leveling control (ALC): ALC disabled (open-loop mode) and ALC enabled (closed-loop mode).

If the ALC is enabled, the ALC is closed, also known as closed-loop mode. The main purpose of the closed loop is to provide greater amplitude accuracy across the whole frequency range, from 250 kHz to 20 GHz. When the ALC is closed, the digital-to-analog converter (DAC) becomes the master reference for output power, which provides greater accuracy. However, the step attenuator hinders the PXIe-5654 switching speed when the ALC is closed.

If the ALC is disabled, the ALC is open, also known as open-loop mode. Open-loop mode is ideal for utilizing modulation capabilities.

You can configure the ALC connection between the PXIe-5654 and PXIe-5696 using the default hardware configuration.

Note Refer to the PXIe-5654 Specifications document for PXIe-5654 switching speed values.