Rockwell Automation T7441A ICS Regent+Plus DC Digital Output Module 24VDC - Manual (Page 2)

DC Digital Output Module (T7441A)
2
Industrial Control Services
Module Operation
A block diagram of a typical 24 VDC digital output module is
shown in Figure 1.
The processor modules send triplicated write data commands
to the output module over the I/O Safetybus. The processors’
addressing data and data write commands are voted by the
module (preventing I/O Safetybus failures upstream from the
module from affecting module operation). The voted result is
then passed to the I/O bus interface logic.
Figure 1. Block Diagram of 24 VDC Digital Output Module.
The voted output data from the I/O bus interface logic is then
used to drive the output circuits. Power MOSFETs are used
on the outputs to convert the logic level output drive signals
to switch 24 VDC power to load devices. These output circuits
provide a very low on state voltage drop and low off state
leakage.