My LM35 sensor ☹
Too much slotting into and out of the breadboard over the last few weeks, has obviously weakened the legs, and the middle (signal) one just broke off right at the base of the device.
Lesson learned - buy myself some simple Vero strip board and strips of header pins, so I can make up my own break-out boards for devices that I salvage from other circuit boards. Not sure if I will be able to save this one or not.
I have seen them listed on ebay for $1.30 if I want to wait another 2 months for them to make their way here from China, but around 6-10 times that price for 'Australian' ebay sellers! I found one Australian supplier independant of ebay, that had them priced a little more realistically at $2.08, but wanted to charge $24 delivery... for something that weighs about 5 grams? Really? But on closer inspection, in turned out that this .com.au company was actually based in Kowloon, Hong Kong - ho hum... Digi-Key in the US are much the same - $2.60 for the part, $24 to deliver it... Living in Australia has its advantages, but boy oh boy - it seems we are a long way away from the rest of the world when it comes to ordering goods online...
Jaycar doesn't sell them, but does sell what is presumably an upgraded version - the LM335Z, for $4.50. This appears to be tied to Kelvin rather than Celsius/Centigrade, putting out 10mV/°K, with it's theoretical output diminishing to 0V at 0°K. However, the device is rated for -40°C to 100°C, so I assume the 'working range' of output voltage is 2.33V to 3.73V - this would mean having to use the 5V "analogReference(DEFAULT)" for analogRead operations, giving an analog step level of 4.88mV equivalent to temperature increments of nearly 1/2°C - mind you, when the accuracy of the device itself is quoted as only within 2-4°C anyway... I might as well just stick my finger in the air and guess!
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