SLUUCF2C January 2021 – May 2022 BQ769142
The BQ769142 device integrates an Undertemperature in Charge (UTC) Protection that triggers an alert or fault when the cell temperature is less than or equal to a programmable threshold TUTC. The TUTC threshold is programmable from –40°C to 120°C in 1°C steps using the Protections:UTC:Threshold configuration register. The UTC protection is enabled using the Settings:Protection:Enabled Protections B:[UTC] configuration bit.
The UTC protection triggers an alert signal when an undertemperature in charge event is first detected, then triggers a fault after a programmable detection delay, UTC_DLY, which can be set from 0 s to 255 s in units of 1 second. The delay is set by the Protections:UTC:Delay configuration register.
When a UTC 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[UTC]. The device recovers when the temperature is greater than or equal to the threshold set by Protections:UTC:Recovery for Protections:Recovery:Time duration.
The temperature used by the UTC 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 that are enabled.