SLUUCW9 December 2023 BQ76972
The BQ76972 device integrates an Overtemperature in Charge (OTC) Protection that triggers an alert or fault when the cell temperature is greater than or equal to a programmable threshold TOTC. The TOTC threshold is programmable from -40°C to 120°C in 1°C steps using the Protections:OTC:Threshold configuration register. The OTC protection is enabled using the Settings:Protection:Enabled Protections B:[OTC] configuration bit.
The OTC protection triggers an alert signal when an overtemperature in charge event is first detected, then triggers a fault after a programmable detection delay, OTC_DLY, which can be set from 0 to 255 seconds in units of 1 second. The delay is set by the Protections:OTC:Delay configuration register.
When an OTC fault is triggered, the device turns off the CHG FET if configured for autonomous FET control, based on the setting in Settings:Protection:CHG FET Protections B[OTC]. The device recovers when the temperature is less than or equal to the threshold set by Protections:OTC:Recovery for Protections:Recovery:Time duration.
The temperature used by the OTC protection is the maximum of all temperature readings that are designated for cell temperature, and can include the internal temperature measurement as well as all external thermistors which are enabled.