04381456 is referenced by 21 patents and cites 2 patents.

The input interface unit of the present invention is equipped with plural input terminals to be connected to external switches respectively, plural output terminals to be connected to input bus lines running to a central control unit (CPU), and plural current-controlling input terminals. These input terminals are divided into plural groups, and the input terminals in each group are connected commonly to each other through pull-down resistors, and then connected through current-carrying switches independently grouped for each terminal group to a power supply equipment built in the unit. And each of these current-carrying switches can be selected and turned on or off for control in response to signals supplied from the central control unit to the current-controlling input terminals.

Title
Input interface unit for programmable logic controller
Application Number
6/245684
Publication Number
4381456
Application Date
March 19, 1981
Publication Date
April 26, 1983
Inventor
Satoshi Yano
Nagaokakyo
JP
Akihiro Yamada
Nagaokakyo
JP
Yoshitane Saito
Nagaokakyo
JP
Agent
Cushman Darby & Cushman
Assignee
Omron Tateisi Electronics Co
JP
IPC
H01H 19/14
H02J 3/00
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