Current control device and method

A current control method for a fan motor, the method comprising steps of:

• a current sampling step for sampling an operating current of the fan motor to generate a sampled current signal, wherein the operating current is controlled by a driving signal of the fan motor;
• a signal generating step for generating a threshold current signal by providing a first resistor having one grounded terminal, and a second resistor having one terminal connected to the first resistor in series and the other terminal for receiving a power so as to generate the threshold current signal;
• a current detecting step for detecting the sampled current signal to generate a protecting signal according to the threshold current signal;
• and
• a current controlling step for stopping generating or decreasing the driving signal according to the protecting signal.

A current control device for a fan motor, comprising:

• a current sampling module for sampling an operating current of the fan motor to generate a sampled current signal, wherein the operating current is controlled according to a driving signal of the fan motor;
• a signal generating module for generating a threshold current signal;
• a current detecting module for receiving the sampled current signal and the threshold current signal and generating a protecting signal according to the threshold current signal and the sampled current signal;
• a current controlling module for receiving the protecting signal, and then stopping generating or decreasing a driving signal according to the protecting signal;
• and
• a voltage sampling module for sampling an operating voltage of the fan motor to generate a sampling voltage signal;
• wherein the signal generating module generates a threshold voltage signal so that the current detecting module receives the sampled current signal, the threshold current signal, the sampling voltage signal, and the threshold voltage signal, and generates the protecting signal according to the sampled current signal, the threshold current signal, the sampling voltage signal, and the threshold voltage signal.