Rockwell Automation 1756-OF8I ControlLogix Eight-channel Isolated Analog I/O Modules - Manual (Page 87)

Rockwell Automation Publication 1756-UM540A-EN-P - May 2014 87
1756-IRT8I Combined Temperature-sensing Isolated Analog Module Chapter 4
Module Block and
Circuit Diagrams The graphics in this section show the 1756-IRT8I module’s block diagrams and
field-side circuit diagrams.
Figure 13 - 1756-IRT8I Module Block Diagram
Isolator
RIUP
Circuit
DC-DC
Converter
Vref
DSP
Nonvolatile
Memory
Field Side Backplane Side
Signal Conditioning
and A/D Converter
CJC 0
Isolated Power
1
7
5
6
B
A
C
K
P
L
A
N
E
Channels 2…5 (not shown - Same diagrams as channels 1 and 7.)
IN_0/RTD D
IN_0(+)/A
Backplane
ASIC
DC-DC
Shutdown
Circuit
System
+5V
ADC CJC
(Channel 0)
IN_0(-)/B
Isolator
DC-DC
Converter
Vref
Signal Conditioning
and A/D Converter
Isolated Power
Channel 0
Channel 1
Channel 6
Channel 7
IN_0/RTD C
IN_1/RTD D
IN_1(+)/A
IN_1(-)/B
IN_1/RTD C
IN_7/RTD D
IN_7(+)/A
IN_7(-)/B
IN_7/RTD C
IN_6/RTD D
IN_6(+)/A
IN_6(-)/B
IN_6/RTD C
CJC 1
Isolator
DC-DC
Converter
Vref
Signal Conditioning
and A/D Converter
Isolated Power
Isolator
DC-DC
Converter
Vref
Signal Conditioning
and A/D Converter
Isolated Power
ADC CJC
(Channel 6)
Status
Indicators
Represents Channel Isolation