The PCB is the wireless (outside) sender unit for an inside/outside thermometer. I want to create a temperature probe from this PCB so that I can measure a temperature in a very specific place.
I need help identifying the temperature sensor component on the PCB. I have had no luck pinning it down with freeze spray. Maybe it's the pair of transistors?
(you can view the images at high resolution by doing right-click > view image)
Following on from the accepted answer (thanks!), I tried moving the component out into a probe.
Temperature agrees with my current wired solution.
Best Answer
The following 4 principles of temperature sensors are most common: thermistor, thermocouple, resistive temperature detector (RTD), silicon bandgap.
Thermocouple and RTD. Not visible on the photos.
In addition, they are rarely found in consumer goods that measure around human temperature range. Thermocouples and RTDs require signal conditioning and excitation circuitry, which increases cost.
prediction: Unlikely
Silicon bandgap temperature sensors are found in consumer goods sometimes. They are packaged like transistors or ICs. They may be embedded inside microcontrollers or ASICs.
prediction: Plausible
Thermistor produce a strong signal and don't require much signal conditioning. It's a cost-effective way of measuring temperature in the human range. These are used in consumer goods.
prediction: Plausible
Hit with chill spray, see what happens.