Temperature sensor LM35DZ

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Frit

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Am I missing something trying to use a LM35DZ temperature sensor by simply putting 12v across it and measuring the voltage on the middle leg? When I try I get 0 volts with ground where I expect 2-3v but 8+ volts to the 12v supply. I have several but all give the same result.
 

hi frit,
The quick reply is, do you have the pins correctly orientated, ie: are the pins reversed.?
E
 

hi frit,
The quick reply is, do you have the pins correctly orientated, ie: are the pins reversed.?
E

Yep, but I did try reversing them just to see. No smoke and no help!
 

You should get about .2V, does the lower voltage range on your meter work?
Frank

Thanks Frank. The meter was jumping a bit around the zero so I reckoned it was zero. Now I've read the data sheet and it only gives 10 mV per degree so like you say 0.2V at 20 degrees. Only I need ten times that.
 

Checked again this morning and the meter reads only around 4mV for four of the five sensors I bought while the last one (not the one I tried with reverse polarity) reads 12v! I suppose that suggests they're all duds.
 

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