Abstract: A fan control circuit with temperature compensation includes an on-off unit and a speed adjustment unit. When determining that a loading is greater than or equal to an adjustable start threshold according to a load signal, the on-off unit controls the fan entering a working mode. In the working mode and determining that the loading is less than a speed-adjusting threshold, the on-off unit maintains a speed value of the fan at a first fixed speed. When determining the loading is greater than or equal to the speed-adjusting threshold, the speed adjustment unit adjusts the speed value according to the loading. The speed adjustment unit generates a speed displacement according to a temperature signal to compensate the speed value.

Abstract: A fan control circuit with temperature compensation includes an on-off unit and a speed adjustment unit. When determining that a loading is greater than or equal to an adjustable start threshold according to a load signal, the on-off unit controls the fan entering a working mode. In the working mode and determining that the loading is less than a speed-adjusting threshold, the on-off unit maintains a speed value of the fan at a first fixed speed. When determining the loading is greater than or equal to the speed-adjusting threshold, the speed adjustment unit adjusts the speed value according to the loading. The speed adjustment unit generates a speed displacement according to a temperature signal to compensate the speed value.

Abstract: In a control circuit and a method for improving the efficiency of a lower load of a power supply device, the power supply device includes power stages, for inputting an input power to the power supply device and producing an output power to drive a load; a control circuit electrically coupled to the power stages for detecting a drive load and issuing a control signal for turning on/off one of the power stages. The control method includes: setting a predetermined output load value by a control circuit; detecting a total output load of the power stages by the control circuit; comparing the total output load with the predetermined output load value; and turning on/off one of the power stages by the control circuit according to a comparison result. The invention reduces the loss of power stages at a low load to enhance the power saving effect and the economic efficiency.