SLUAAJ8 January   2023 BQ25180

 

  1.   Abstract
  2.   Trademarks
  3. 1Temperature Sensing
    1. 1.1 Temperature Sensing and JEITA Standard
    2. 1.2 Current Driven TS Function
    3. 1.3 Calculating RS and RP
  4. 2BQ25180 and NTC Monitoring Calculator
  5. 3Example of TS Circuit Design
  6. 4References

2 BQ25180 and NTC Monitoring Calculator

The BQ25180 implements a 38 uA current source for biasing the resistor network. The voltage thresholds are tuned to work with a thermistor with a β of 3435 that is calibrated to 10 k Ω at 25°C. As mentioned before, external resistors can be used to allow the BQ25180 to work with other NTCs. Additionally, the BQ25180 allows for adjustable HOT and COLD voltage thresholds for applications which require different ranges. The COOL and WARM thresholds can selectively be disabled through I2C.

TI offers the External NTC Monitoring (TS) Calculator for the BQ25180 to facilitate configuration checking. This calculator can be accessed by selecting the calculator icon from the left menu bar on the BQ25180 TI Charger GUI page.

Figure 2-1 Menu Logo

The planned NTC’s specifications can be entered as well as any calculated R­S values, RP values, and register configurations. Once all configuration specifications have been entered, pressing the calculate button populates the outputs with the expected temperatures in Celsius at which the device is expected to enter and exit JEITA thresholds.

Figure 2-2 External NTC Monitoring (TS) Calculator Page View