AVR-Chat

On Tue, 02 Dec 2003 10:26:03 -0000, you wrote:

>In MCUs DS18S20 is a much better solution than LM35 since it gets rid 
>of the inaccuracies assiciated with ADC (though it is slightly 
>expensive).
>Resolution upto 0.0625 DegC can be obtained.
>It comes calibrated and the output is digitized - no further 
>calibration is required.
>it comes in TO-92 package (the popular small transistor pack) which is 
>very handy to integrate into a probe or similar application (ofcourse 
>LM35 also comes in TO92).
>NTC may turn out to be a headache on linearization (calibration).
>If you are not worried about the precise reading, you can go for a 
>thermistor(NTC/PTC)without linearization - but you need a current 
>source to convert the resistance to a voltage and again the nuances 
>associated with ADC.
>The preference shall be DS18S20, LM35 & Thermistor in that order.

Unless you are going to production where cost is an issue, in which case the order of preference is
the reverse. 
Thermistors are very cheap, and their nonlinearity etc. can be taken care of in software easily
enough.