Abstract: A method of starting and/or driving a fan assembly, the fan assembly comprising a BLDC motor having one or more coils, and a bearing comprising a lubricant. The method comprises performing a special action for intentionally heating up the one or more coils and thereby indirectly heating up the lubricant. The method may comprise measuring a temperature of the bearing, or measuring a value related to said temperature, and performing the special action only if said temperature is below a certain threshold temperature. Performing the special action comprises setting an off-time to a first predefined value and setting an on-time to a second predefined value, the first and second predefined value having a first ratio. Starting the motor comprises setting the off-time to a third value and setting the on-time to a fourth predefined value, the third and fourth predefined value having a second ratio larger than the first ratio.

Abstract: A method of starting and/or driving a fan assembly, the fan assembly comprising a BLDC motor having one or more coils, and a bearing comprising a lubricant. The method comprises performing a special action for intentionally heating up the one or more coils and thereby indirectly heating up the lubricant. The method may comprise measuring a temperature of the bearing, or measuring a value related to said temperature, and performing the special action only if said temperature is below a certain threshold temperature. Performing the special action comprises setting an off-time to a first predefined value and setting an on-time to a second predefined value, the first and second predefined value having a first ratio. Starting the motor comprises setting the off-time to a third value and setting the on-time to a fourth predefined value, the third and fourth predefined value having a second ratio larger than the first ratio.

Abstract: The method of the present invention for switching an output driver of the type comprising an n-mos transistor and a p-mos transistor configured in a push-pull arrangement operates by directly monitoring the level of the output signal OUT. The method comprises slowly switching off the input to the initially designated active transistor; monitoring the variation in output voltage level in response thereto; and when a desired change in output level is detected the switching the initially designated output transistor on completely and fast. Using this method the parasitic currents in the diodes are much smaller in time and amplitude.