Patent ID: 6674243
Filing Date: 2004-01-06
Classification: H05B,Y02B

Abstract:
An electroluminescent (hereinafter referred to as â€œELâ€ ) driving circuit comprising:an EL element, a voltage set-up coil which generates pulsating voltage for turning on the EL element, an oscillating circuit for generating a reference signal, a dividing circuit for dividing a clock generated by the oscillating circuit into at least two kinds of frequency clocks, a first switching circuit for switching current which flows the voltage set-up coil by a higher frequency clock of the two kinds of frequency clocks divided by the dividing circuit, a second switching circuit for switching polarity of voltage applied to the EL element by a lower frequency clock of the two kinds of frequency clocks, a control circuit for switching connection between the dividing circuit and the first switching circuit, and connection between the dividing circuit and the second switching circuit at the same time by a control signal which turns on and off the EL element, and a suppressing circuit for suppressing a counter electromotive force created in case of turning off the EL element below withstanding voltage of the first switching circuit.