ADLINK Technology MCM-100, User Manual

Page: 51 / 117

Operation 35
MCM-100/102
4 Operation
Operation of the MCM-100/102 is described here to assist in
configuration and programming of the module. Functions
addressed include analog input and GPI/O.
4.1 Analog Input
4.1.1 Analog Input Front End Configuration
Figure 4-1: MCM-100/102 Analog Front End
Input Configuration: Differential/Pseudo-Differential
Differential input mode provides anode and cathode inputs of the
BNC connector that respond to signal voltage differences
therebetween. If the signal source is ground-referenced, the
differential input mode can be used for common-mode noise
rejection.
If the signal source is a floating signal, setting pseudo-differential
input mode will provide a reference ground connected to the
cathode input of the BNC through a 20 k
Ω resistor.
Recommended configurations for the signal sources are as
follows.
Table 4-1: Signal Source-Card Configuration
Signal Source Card Configuration
Floating Pseudo-differential
Ground-reference Differential
Calibration
Circuit
24 Bit ADC
AI
IEPE
Circuit
AC
Coupling
circuit
Diff input
ADC Driver
Differential/
Psuedo-
differential
Switch
Circuit