Patent ID: 7368851

Claim:
An ultrasonic driving device with current limiting protection, comprising: a signal generating module for providing an alternating current first drive signal; a first protection module connected electrically to said signal generating module so as to receive the first drive signal therefrom; an output module connected electrically to said first protection module, wherein said first protection module detects an operating current of said output module and provides the first drive signal to said output module when magnitude of the operating current of said output module is smaller than a first threshold current value, wherein said output module adjusts amplitude of the first drive signal received from said first protection module to result in a second drive signal, and wherein said first protection module stops providing the first drive signal to said output module such that said output module ceases to generate the second drive signal when the magnitude of the operating current of said output module is not smaller than the first threshold current value; and an ultrasonic transducer connected electrically to said output module so as to receive the second drive signal therefrom and so as to output ultrasounds, the frequency of which corresponds to that of the second drive signal.