Overview
PDM microphones typically have low power output
drivers, designed for the very short wiring connection
to a downstream circuit within a device.
Many testing situations require relatively long cable
runs between the PDM DUT and the analyzer. A
typical example is the testing of a PDM microphone
within an acoustic chamber, while the analyzer is
located outside of the chamber at some distance. The
PDM Line Driver boosts the PDM data signal from
the microphone to enable this longer cable run while
maintaining data integrity.
Using the PDM Line Driver
Place the PDM Line Driver near the PDM DUT. Con
nect the PDM DUT to the PDM Line Driver using
three short 50 Ω coaxial cables. We recommend using
the 36 cm (14 in.) BNC to BNC cables provided with
the PDM Line Driver.
PDM Line Driver User’s Guide
The PDM Line Driver (model PDM-DRVR) enables long
cable runs between a PDM Device Under Test (DUT) and
the PDM input on an Audio Precision analyzer.
APx analyzer
PDM module
PDM
line driver
PDM
microphone
Vdd line
Bit clock line
Data line
