©
National Instruments Corporation
3-1
3
Theory of Operation
This chapter contains a functional overview of the SCXI-1121 module and
explains the operation of each functional unit making up the SCXI-1121.
Functional Overview
The block diagram in Figure 3-1 illustrates the key functional components
of the SCXI-1121.
Figure 3-1.
SCXI-1121 Block Diagram
SCXIbus
Digital
Interface
and
Control
Timing
and
Analog
Output
Stage
Fr
ont Connector
Rear
Signal Connector
Isolated Section
Nonisolated
Section
Input channel 0
Excitation 0
Input channel 3
Excitation 3
Temperature sensor
–
+
+
+
+
–
–
–
•
•
•
•
–
+
+
+
•
•
•
•
