Hello
I Have a design that needs to have very low resistance 0.2 ohms at -25 deg.Can i get help on how to select the same.

 

Hello sneha. Welcome.

I am sorry I haven't yet seen one but may be other members had. Give it some time for others to respond.

 

Think the lowest ntc is a 2k2 @ 25C, ntcs go higher in resistance with lower temps, what is the design for?

 

It is used to to see when the cooling ability of the system breaks down.By knowing the power the system can withstand the resistance is calculated to 0.2ohms.I need to select the NTC accordingly.

 

I can bid at .7 ohms, but better to post the literature.

 

Thanks for the inputs.I will check if these suit my application.

 

Are you sure you aren't looking for a protection type thermistor? eg.
http://uk.rs-online.com/web/p/produ...X2VHBmSCaAtPiU4_s_n_aBLQBrk9LG5wXSjNl-VPD_BwE
those types of device have quite low resistances but they are not intended for temperature measurement rather for circuit protection.

 

Yes my application is for temp measurement and not circuit protection.

 

Why must the thermistor be such a low value? Normally in most measurement scenarios people want to have a large thermistor value to reduce self heating and save power on the measurement system itself.

 

Why must the thermistor be such a low value? Normally in most measurement scenarios people want to have a large thermistor value to reduce self heating and save power on the measurement system itself.

Ummm...not always. Driven with a constant current, lower R results in proportionally less power, as P=IR.

OTH, I am not sure the OP understands what he really needs. 0.2 ohms at -25C to seems quite unusual.