SLUAAL4 August   2022 BQ21040

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2How Temperature Sensing Works on the BQ21040
    1. 2.1 With Adapter Present
    2. 2.2 Without Adapter Present
  5. 3Example Application
    1. 3.1 Required Devices
    2. 3.2 Setup
  6. 4Procedure
    1. 4.1 Detecting Adapter Removal
    2. 4.2 Detecting Adapter Insertion
    3. 4.3 Logical Flowchart
  7. 5Summary
  8. 6References

2.1 With Adapter Present

Typically, when monitoring temperature on the BQ21040, a 50uA current is supplied at the TS pin. This current then travels through an NTC thermistor to ground. As the resistance of the NTC varies with temperature, so does the voltage drop across it. This voltage drop is then measured to derive the temperature.