I have absolutely no experience with temperature sensors. I am interfacing with a STLM20 temperature sensor, the datasheet can be found here:
http://www.st.com/web/catalog/sense_power/FM89/SC294/PF129199

anyway the connection is quite simple, I have a question regarding the transfer function.....what is it and how can I use it to measure temperature?

 

The datasheet is pretty clear. What part do you not understand?

 

how to use the transfer function provided to measure temperature?

 

y = mx + b

 

Look at Table 2 in the datasheet. Pick the temperature range that best fits your application. Use the corresponding conversion formula.


Or better yet, use an LM35 or LM34...much simpler.

 

Yep, LM35. Each 10mV = 1 degree C.

It doesn't get much better than that.

 

I agree, 10mV per °C is so much easier that 11.77mV per °C. You can just measure voltage with a cheap DMM and you're done.

I do see one advantage to the OP's chip - it can use a single supply over a much wider temp range.