I am in search of linear NTC Temp. Sensor with 5 kohm at 25 deg C.

 

Have you tried http://www.newark.com ?

they have plenty of NTC and may even have links to various manufacturers.
May be a non-std value at that temp. so you may have to go to specific vendor to special order what you want.

Try this contact
mailto:[email protected]

Also I did find a NTC 5kohm device at www.newark.com
made by fenwal electronics

I did not go much further, but my understanding is that thermistors are specified at 25 degC unless otherwise stated.

matt
[email protected]

 

Thermistors are inherently non-linear, but very sensitive. Of the NTC devices I'm familiar with, none are in this range and used in the same manner. Which alternative you use would depend strongly on your application. For measurement applications, I tend towards using a three
terminal device with an A/D channel and doing the math in the code.

Regards

cww

 

You're right, they are non-linear, and most of the manufacturers I have worked with provide the calib. coefficients.

matt

 

The thermistors are non-linear but there are manufacturers who produce thermilinear networks with one or two thermistors and a couple of resistors. In simplest form one of each. They are packaged just as thermistors and are normally used only over small temperature ranges. Certainly both Fenwal and YSI make them. YSI don't have any that are 5k Ohms at 25 deg C. Some of theirs are 6k if that is usable.

Vince