SLUSCC7C July 2016 – June 2018 TPS546C23
The OT_WARN_LIMIT command sets the value of the temperature, in degrees Celsius, that causes an overtemperature warning condition, when the sensed temperature from the external sensor exceeds this limit. Upon triggering the overtemperature warning, the device takes the following actions:
Once the overtemperature warning is tripped, the warning flag is latched until the external sensed temperature decreases 20°C from the OT_WARN_LIMIT.
The OT_WARN_LIMIT must always be less than the OT_FAULT_LIMIT. Writing a value to OT_WARN_LIMIT greater than or equal to OT_FAULT_LIMIT causes the device to set the CML bit in the STATUS_BYTE and the invalid data (ivd) bit in the STATUS_CML registers as well as assert the SMBALERT signal. In such case, the register content will remain unchanged. This behavior can be overridden by the user setting Data Limit Override (DLO) in MFR_SPECIFIC_21.
The default OT_WARN_LIMIT is mathematically derived from the EEPROM backed OTF limit by subtracting 25 from (4Fh) OT_FAULT_LIMIT to reach the default OT_WARN_LIMIT. If the calculated OTW is less than 100°C, then the default value is set to 100°C. OTW=max(OTF-25, 100)
The OT_WARN_LIMIT takes a two byte data word formatted as shown below: