SLUUBY1B December 2020 – April 2022 BQ76942
The BQ76942 device integrates an Undertemperature in Discharge (UTD) Protection that triggers an alert or fault when the cell temperature is less than or equal to a programmable threshold TUTD. The TUTD threshold is programmable from -40°C to 120°C in 1°C steps using the Protections:UTD:Threshold configuration register. The UTD protection is enabled using the Settings:Protection:Enabled Protections B:[UTD] configuration bit.
The UTD protection triggers an alert signal when an undertemperature in charge event is first detected, then will trigger a fault after a programmable detection delay, UTD_DLY, which can be set from 0-sec to 255-sec in units of 1-sec. The delay is set by the Protections:UTD:Delay configuration register.
When a UTD fault is triggered, the device will turn off the DSG FET if configured for autonomous FET control, based on the setting in Settings:Protection:DSG FET Protections B[UTD]. The device will recover when the temperature is greater than or equal to the threshold set by Protections:UTD:Recovery for Protections:Recovery:Time duration.
The temperature used by the UTD protection is the minimum 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.