ADLINK PCI-9527 - Manual (Page 40)

28 Operation Theory
PCI-9527 ADLINK Technology Inc.
User’s Manual Copyright 2010
3.3 Analog Output Channel
3.3.1 Analog Output Front-End Configuration
Output Configuration - Differential, Pseudo Differential
The differential output mode provides the anode and cathode out-
puts of the BNC connector that respond to the DAC outputs volt-
age difference between them. If the DUT inputs are ground-
referenced, the differential output mode can be used for the elimi-
nation of measuring errors which caused by ground loops.
If the DUT inputs are in a floating system (ex. a floating earphone),
setting to pseudo-differential output mode will provide a reference
ground connected to the cathode output of the BNC through a
50ohm resistor. This will prevent the floating system from drifting
over its input common-mode range.
The recommended configurations respect to the input reference
types of DUT are as followed.
DUT Input Reference Type Card Configuration
Floating Pseudo Differential
Ground-Reference Differential
Table 3-4: Output Configuration
DAC
CH0
AO CH0+
AO CH0- / AOGND
Attenuator
x1
x0.1
x0.01
Differential
Driver
XLR
Switch
IV
Converter
DAC
CH1
Differential
Driver
IV
Converter
AO GND
CHASSIS
GND
AO CH1+/ AO CH0-
AO CH1- / AOGND