What is integrated temperature sensor?
The main mechanism of temperature detection is the internal current source and ADC of the integrated temperature sensor, The integrated temperature sensor works as follows:
Using the semiconductor PN junction is positive, With different conduction voltage drop characteristics of the temperature measurement. By the semiconductor PN bump-ampere characteristic curve:
ID: Diode forward current,
IS: reverse saturation current of diode,
VD: Forward voltage drop of diode.
N: ideal for diodes (generally about 1),
K: Boltzmann constant (1.38 × 10-23 joules / K).
T: absolute temperature K,
Q: the charge of an electron (1.6 x 10-19 C)
The internal current source of the integrated temperature sensor sends two different currents. The ADC reads the different diode forward voltage drop at different currents. That is, when the current source sends a high current IDH, the ADC reads VDH.