7 years, 1 month ago.

MBED application board LM75B temp wrong

I'm seeing 32.88 or 32.75 on the LCD, or about 91 degrees F. This is wrong. My thermometer reads 80 degrees. So the LM75B is 11 degrees high. Can anything be done? I have not checked any other sensors on the board. I'm not a happy camper.

Don

2 Answers

7 years, 1 month ago.

Isn't it due to the heat from nearby components? If you put a fan on it, does it change?

7 years, 1 month ago.

Yes, a fan cools it down, but the temperature is way off. Right now the room temperature is 76 F, or 24 C. I see 29 C. Also, after compile, why so I see so many warnings, all referring to the LCD. I do get "Success" however.

Then it is off simply because the sensor is hotter than your room temperature, not much you can do about it, besides putting it in a different location if you would make your own PCB.

Regarding the LCD, iirc some stuff is declared not strictly in the correct order there, which generate the warnings. It should still work fine.

posted by Erik - 21 May 2013