Rockwell Automation 1769-OF4VI Compact I/O Isolated Analog Modules - Manual (Page 14)

Publication 1769-UM014B-EN-P - May 2010
1-6 Overview
Module Operation
The following sections describe the input and output modules’ block diagrams.
Input Module Block Diagram
The input module’s input circuitry consists of four isolated-differential analog
inputs each with it’s own analog-to-digital (A/D) converter. The A/D
converter reads the selected input signal and converts it to a digital value that is
presented to the controller.
Figure 1.4 1769-IF4I Block Diagram
ADC
OPTO
LED
OPTO
DC / DC
Converter
High
Impendence
Ch0+
Ch0-
Ch0_iRtn
ADC
OPTO
OPTO
DC / DC
Converter
High
Impendence
Ch0+
Ch0-
Ch0_iRtn
CPU
ASIC BUS