The TSn pins must connect with a thermistor or resistor to the reference power pin for the associated cell group, as shown in the applications diagram. A resistor must be connected for normal operation even if external temperature measurement is not used. When thermistors are removable, they should be substituted with a test resistance at board test to prevent XREADY faults during test. The TSn pins should not be pulled below their reference power pin or the device may not start properly or the ADC may not operate properly.

A capacitor across the thermistor is not required but may filter noise picked up by thermistor leads. The thermistor is biased 37.5 ms before measurement begins, so a 4.7-nF capacitor, such as is used on the evaluation module or smaller, allows many time constants for settling before measurement.

TS1 is also used to boot the part. A rising edge is required for boot. A high level maintained on TS1 does not prevent shutdown or waking the part. A voltage level maintained on the TS1 pin after boot affects the voltage on the thermistor and the temperature determined by the MCU if external temperature sensing is used in normal operation.