Patent ID: 6011371
Filing Date: 2000-01-04
Classification: G06F,H05K,Y10S

Abstract:
An electronic device, comprising:a case having a local environment temperature within the case a reference temperature and a steady state local environment temperature condition when the local environment temperature equals the reference temperature;a fan having a speed and a rate of change of fan speed;a temperature sensor for detecting the local environment temperature inside the case, the temperature sensor exhibiting a lag time for indicating actual local environment temperature; andcontrol circuitry connected to the temperature sensor and the fan, the control circuitry implementing closed loop control over the fan to vary the speed of the fan in a manner which cancels out the lag time of the temperature sensor during the steady state local environment temperature condition of the electronic device, wherein during the steady state local environment temperature condition of the electronic device the rate of change of the speed of the fan varies in proportion to variation in detected local environment temperature.