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Opto-Isolated Digital I/O Signal Conditioning Boards for Small Form Factor Embedded Computer Systems

May 1, 2012, Arlington, TX – WinSystems introduces today two new optically isolated signal conditioning and termination boards for OEM embedded computer system designers.  These boards are needed in applications requiring signal isolation between a computer and its monitoring points.  Isolation creates a barrier which will eliminate common mode voltage and also prevents ground loops on digital signals plus provides safety for industrial applications.  The ISM-TRM-ISO-IN provides 24 lines of optically isolated and digitally debounced inputs to provide easy connections and signal conditioning from field wiring.  The ISM-TRM-ISO-OUT provides 24 lines of optically isolated outputs.  To interface with field wiring, the boards use 3.5mm pitch, industry-standard, pluggable connectors to insure reliable connection with easy removal and insertion. 

Each input pair of the ISM-TRM-ISO-IN has configuration flexibility to support either an active high or active low signal from 5 to 30 volts.  Every input line is optically isolated from the others and from the computer interface circuits.  The isolation voltage rating between the input and output of the photocoupler device exceeds 2500V.  Then each input line is wired to a contact bounce eliminator.  Its purpose is the elimination of extraneous level changes that result when interfacing with mechanical contacts such as from switches or relays.  This circuit removes bounce on both the “make” and “break” of a contact closure.

Each output line of the ISM-TRM-ISO-OUT is optically isolated from the embedded computer’s digital I/O interface circuit.  The isolation voltage rating between the input and output of the photocoupler device exceeds 2500V.  Each output has a NPN Darlington transistor pair with an integral clamp diode for switching inductive loads and transient suppression.  The collector-emitter voltage can withstand up to 30 volts and each output is capable of sinking 500 mA of current required by most relays.

Both boards measure 3.6 x 3.8 inches (90 x 96mm) and have the same mounting hole pattern as PC/104 modules.  The ISM-TRM-ISO-IN and ISM-TRM-ISO-OUT boards can be placed on the top or bottom of a PC/104 stack.  These cards will also easily work with other computer form factors such as EPIC and EBX mounted on the PC/104 stack or as independent standalone signal conditioning modules for even more versatility.

Both ISM-TRM-ISO-IN and ISM-TRM-ISO-OUT signal conditioning modules are RoHS-compliant and can operate over an industrial temperature range of -40° to +85°C.

PRICING AND AVAILABILITY

The ISM-TRM-ISO-IN is priced at $209 (qty. = 1) and the ISM-TRM-ISO-OUT is priced at $149 (qty = 1).  Delivery is from stock. 

Product pages

ISM-TRM-ISO-IN: http://www.winsystems.com/products/misc/ISM-TRM-ISO-IN.cfm 

ISM-TRM-ISO-OUT: http://www.winsystems.com/products/misc/ISM-TRM-ISO-OUT.cfm 

ABOUT WINSYSTEMS

WinSystems, located in Arlington, Texas, designs and manufactures industry-standard PC/104, PC/104-Plus, EPIC, EBX, Pico-I/O, SUMIT-ISM, and STD Bus single board computers (SBCs), I/O modules, and enclosures for use by OEMs and system integrators worldwide.  We have served the industrial, transportation, pipeline, COTS, communications, and medical markets for over 30 years.  We are an employee-owned company.

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