73M1966B Evaluation Kit User Manual
UM_1966B_024
12
Rev. 1.0
4 Using the Demo Boards
This section provides advice for using the 73M1966B Evaluation Kit with the Wandel & Goltermann
PCM-4.
It is assumed that the connections described in
Getting Started
have been made, that the GUI has been
installed following the instructions in the
73M1866B/73M1966B GUI User Guide
, and that
power
has been
applied to the 73M1966 Demo Motherboard.
Initialize and configure the Demo Board for your application using the GUI. See the
73M1866B/73M1966B
GUI User Guide
. The GUI software includes example scripts that configure the Demo Board for specific
purposes.
The following is a suggested list of tests that can be performed using a PCM measuring set such as the
W&E PCM-4:
•
TX Gain – Tests the digital input to analog output level and its conformance to the required
specifications. The effect of the gain setting bits can also be tested (DAA1:0, TXboost).
•
RX gain- tests the analog input to digital output level and conformance to the required specifications.
The effect of the gain setting bits can also be tested (RXG1:0, RX boost).
•
TX/RX Gain versus Frequency – Tests the gain variation versus frequency across the audio band.
Shows the passband ripple and adherence to the frequency response template.
•
TX/RX Gain Linearity – Tests the gain linearity over the receive level dynamic range. Also sensitive
to the RX DC offset and noise.
•
Return Loss – Indicates the matching of the DUT impedance to the standard's reference impedance.
Only impedances supported by the specific W&G PCM-4 can be tested. Other impedances must be
tested using an impedance bridge and adjustable reference impedance. Most W&G PCM-4s support
600, 850 and 900 Ohms plus one "complex impedance," which can be ETSI, German or "custom"
impedance. Some W&G PCM-4s may not support a complex impedance at all.
•
Return Loss – TX digital to RX digital test to determine the amount of transmitted signal is reflected in
the receive channel. A proper reference impedance and DC supply must be connected at the analog
port of the DUT.
•
TX/RX Total Distortion – Tests the dynamic range of the TX and RX channels and the effects of the
compander. This test is also sensitive to the RX DC offset and noise. Must comply with the test
template.
For information about typical test results and other relevant tests, refer to
73M1966B Performance
Characterization
.