Patent ID: 7573220

Claim:
An electronic circuit for self-calibrating an electronic cooling fan, comprising: a temperature-sensing subcircuit for measuring the temperature of a device, region or circuitry to be cooled; a microcontroller connected to the temperature-sensing subcircuit, for controlling signals within the circuit, adjusting measured voltage values with an offset value, and determining whether operation should proceed in calibration mode or in operation mode; and a fan, with an electronically controlled motor, connected to the microcontroller, for providing airflow to the subject device, region or circuitry to be cooled, wherein the microcontroller measures the voltage value across the temperature-sensing subcircuit and computes the offset value as a difference between the measured voltage value and an ideal voltage value during the calibration mode, and adjusts subsequently measured voltage values with the offset value, wherein the circuit is capable of calibrating itself to account for tolerances in its temperature reading sensitivity by reading temperatures of the subject device, region or circuit to be cooled and then using calibration data in regulating fan-motor speed thereafter.