Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!crdgw1!uunet!keinstr!chaplin
From: chaplin@keinstr.uucp (chaplin)
Newsgroups: sci.electronics
Subject: Re: Thermocouple output to digital
Message-ID: <1991Apr30.140257.247@keinstr.uucp>
Date: 30 Apr 91 14:02:57 GMT
References: <1991Apr25.182617.15874@hubcap.clemson.edu> <7392@oasys.dt.navy.mil>
Organization: Keithley Instruments, Cleveland, Ohio
Lines: 27

In article <1991Apr25.182617.15874@hubcap.clemson.edu>
  jelynch@hubcap.clemson. edu (james e lynch) writes:
>I'm constrained to use a type K thermocouple to measure temperature.
>The thermocouples output has to be digitized but not displayed (it
>feeds into a data acquisition system).  I am willing to add an ADC
>to the data acquisition system, but I need some help going from the
>thermocouple to copper leads feeding the ADC.  Is there a single package
>solid state device that converts thermocouple signals to mVolts (that
>is, a device that has the compensation for the terminal dissimilar
>metals potential).  Or better yet, a simple and cheap pre-packaged
>thermocouple in / digital out board module.  I realize that equipment
>to perform the task is available from Omega, but I don't need the
>extra features and most importantly I can not afford the cost.  Please
>forward all comments to:  jelynch@hubcap.clemson.edu

About 8 years ago I designed a data acquisition system using just such
an IC.  It contained a temperature sensor and converted a type T
thermocouple signal to 10mV/degC.  It was made by Analog Devices, but
their latest data book does not list it, and I can't remember the part
number.  Analog Devices has dropped a lot of products from their line
lately.  An analog guru friend of mine says that Linear Technology is
starting to introduce similar products.  You might check with them.
-- 
Roger Chaplin / Instruments Division Engineering / uunet!keinstr!chaplin
CI$: 76307,3506 / voice: (216) 498-2815 / FAX: (216) 248-6168
"In the last analysis the customer is the independent auditor.  In the
merciless light of real use, every flaw will show." - Frederick P. Brooks, Jr.