I have this thermometer. It overestimates room temperature by +3C.
It seems to be using DS18B20 but pull up resistor on the board is 10K instead of 2.7K required for 3V.
I replaced it with 2.7K and it was displaying temperature around -3C in room and when I used 4.7K it displayed temperature around +10C in room.
I don't know if this can be fixed so I decided to take DS18B20 away from thermometer and use it in Arduino project.
I would like to know how to communicate with this LCD but I cannot find any info on model name. Any ideas guys?
Edit:
Actually it is using NTC thermistor (10K/3435) so I need to put in resistor with lower resistance value. I'm still curious how to communicate with the display?
Well, it's an ASIC, so it gives a number according to a specific resistance which you connect to it, so you would have to emulate a resistance in order to have it indicate.
Now how does it measure the resistance? well, it presumably either applies a constant current to the resistance, or puts it in series with another fixed resistance and in either case, measures the voltage across the thermistor. So presumably if you apply a varying voltage across the thermistor wires - in the right polarity - it will indicate certain numbers,
However it is possible that it does not apply the voltage constantly, but switches it on for short periods of time and then off again, to conserve current from the battery, so that might be tricky.