Power supply controller
A power supply controller controls operation of a power supply apparatus that generates an output voltage from an input voltage. The power supply controller includes a temperature determination circuit configured to determine to which of a plurality of temperature ranges a temperature of the power supply controller belongs, a measurement circuit configured to measure, for each of the plurality of temperature ranges, a period for which the temperature of the power supply controller belongs to the temperature range, and a nonvolatile memory configured to store a measurement result of the measurement circuit.
1 . A power supply controller configured to control operation of a power supply apparatus that generates an output voltage from an input voltage, the power supply controller comprising:
a temperature determination circuit configured to determine to which of a plurality of temperature ranges a temperature of the power supply controller belongs;
a measurement circuit configured to measure, for each temperature range of the plurality of temperature ranges, a period for which the temperature of the power supply controller belongs to the temperature range;
a nonvolatile memory configured to store a measurement result of the measurement circuit; and
a memory controller configured to control writing to the nonvolatile memory,
wherein the measurement circuit is configured to output, for each temperature range of the plurality of temperature ranges, a count-up signal to the memory controller each time a predetermined unit of time elapses while the temperature of the power supply controller belongs to one of the plurality of temperature ranges, and
the memory controller is configured to, in response to receiving the count-up signal, update a cumulative drive time corresponding to the one of the plurality of temperature ranges stored in the nonvolatile memory.
2 . The power supply controller according to claim 1 , wherein
the nonvolatile memory stores a cumulative drive time for each of the plurality of temperature ranges, and
the cumulative drive time for each of the plurality of temperature ranges represents a cumulative value of the period for which the temperature of the power supply controller belongs to the temperature range in a period for which the power supply controller is driven.
3 . The power supply controller according to claim 2 , further comprising
a signal output control circuit operable to output a specific signal to an external device of the power supply controller, wherein
the signal output control circuit decides whether to output the specific signal based on each of the cumulative drive times stored in the nonvolatile memory.
4 . The power supply controller according to claim 3 , wherein the signal output control circuit determines whether the power supply controller has reached an end of its service life based on each of the cumulative drive times stored in the nonvolatile memory, and decides whether to output the specific signal based on a result of the determination.
5 . The power supply controller according to claim 4 , wherein the signal output control circuit derives a weighted sum by performing weighted addition on a plurality of the cumulative drive times for the plurality of temperature ranges, and determines whether the power supply controller has reached the end of its service life based on a result of comparison between the weighted sum and a predetermined threshold value.
6 . The power supply controller according to claim 1 , further comprising
a temperature sensor configured to output a signal corresponding to the temperature of the power supply controller; and
a temperature anomaly detection circuit configured to detect a temperature anomaly of the power supply controller based on an output signal of the temperature sensor, wherein
the temperature determination circuit determines to which of the plurality of temperature ranges the temperature of the power supply controller belongs by using the temperature sensor.
7 . The power supply controller according to claim 1 , further comprising
an anomaly detection circuit configured to detect a predetermined anomaly, wherein
when the anomaly detection circuit detects the anomaly, information indicating that the anomaly is detected is stored in the nonvolatile memory.
8 . The power supply controller according to claim 1 , wherein
the power supply apparatus includes regulators for a plurality of channels and generates the output voltage from the input voltage for each of the channels, and
the power supply controller controls operation of each of the regulators for each of the channels.
9 . The power supply controller according to claim 1 , wherein
the temperature determination circuit is configured to output to the measurement circuit a classification signal indicating to which of the plurality of temperature ranges the temperature of the power supply controller belongs.