JAJSFE5C October 2009 – May 2018 TPS65720 , TPS65721
PRODUCTION DATA.
The internal Multiplexer switches the analog voltage on Pin BAT (battery voltage) or on pin TS (battery NTC) to pin TS_OUT. The input is selected by Bit <OPAMP_MUX> in register CONTROL1. The input voltage range of 2.5 V to 4.5 V on pin BAT is internally scaled to a voltage of 0 V to 1.4 V on pin TS_OUT. If the battery temperature is selected as the input by setting <OPAMP_MUX> = 1, a temperature range of –20°C to 60°C is scaled to a voltage of 0 V to 1.4 V on pin TS_OUT. If the charger is not active, the internal current source for the NTC inside the battery pack is enabled automatically if the multiplexer is enabled with <OPAMP_EN> = 1 AND temperature measurement is selected by <OPAMP_MUX> = 1. If the analog multiplexer is disabled with <OPAMP_EN> = 0, the output VBAT/TS_OUT is shorted internally to GND, allowing for offset correction at the ADC. See Figure 15 for more details.
The transfer function for the battery voltage is given in the Figure 16: