To provide a fan motor drive device capable of effectively reducing the generation of noise at a time of starting a system or during a standby time.
The driving device 6 is electrically connected between a PWM signal generator 7 and a controller 2. The drive device includes a converter 61 which outputs a first reference voltage, based on the duty cycle of a PWM signal generated by the PWM signal generator 7; and a reference voltage generator 62 which generates a second reference voltage based on an external power source 8, and a comparator 63 wherein a first input terminal is electrically connected to the converter 61, a second input terminal is electrically connected to the reference voltage generator 62 and the output terminal is electrically connected to the controller 2, and then the output terminal outputs a variable drive signal to the controller 2, after the first reference voltage has become higher than the second reference voltage, to control the rotation speed of a fan motor 1.
| JPS58133189 | ROTATION CONTROLLING DEVICE |
| JPH01226012 | COOLING DEVICE FOR ELECTRONIC APPARATUS |
| WO/2011/148852 | MOTOR CONTROL DEVICE |
HSIEH TSUNG-JUNG
HUANG YAO LUNG
HUANG WEN-HSI
Shimizu Sakaematsu
Kuniaki Toyama
Masayoshi Yoshida