SLVSDF3F MARCH 2017 – JANUARY 2019 TPSM846C23
The TPSM846C23 device also provides temperature telemetry and programmable internal overtemperature fault or warning thresholds using measurements from an internal temperature sensor. The temperature-sensor circuit applies two bias currents to an internal diode-connected NPN transistor and measures ΔVBE to infer the junction temperature of the sensor. The device then digitizes the result and compares it to the user-configured overtemperature fault and warning thresholds. When an internal overtemperature fault (OTF) is detected, power conversion stops until the sensed temperature decreases by 20°C. The READ_TEMPERATURE_1 (8Dh) register is continually updated with the digitized temperature measurement, enabling temperature telemetry. The OT_FAULT_LIMIT (4Fh) and OT_WARN_LIMIT (51h) commands set the overtemperature fault and warning thresholds through the PMBus interface. When an overtemperature event is detected, the device sets the appropriate flags in STATUS_TEMPERATURE (7Dh) command and triggers the SMBALERT signal if it is not masked.