| 摘要 |
PURPOSE: To provide a bridge circuit to charge an electrostatic capacity of an EL lamp with a fixed current as well as to generate a high DC voltage capable of alternately charging and discharging the EL lamp. CONSTITUTION: When a transistor Q1 is switched between on and off at high frequencies with a high frequency oscillator 10, a capacitor CS connected with an inductor L1 through a diode D17 is charged by the repeated charging/ discharging of the inductor L1 . A bridge circuit receives two pairs of low frequency square-wave pulse signals with an opposite polarity from a low frequency oscillator 15. Each signal is given to one of two legs in series of two facing branches. Each branch is connected between the high DC voltage and the ground. Each leg contains two switching FET transistors and sources of current Q2 , QS. An electroluminescent lamp is connected between legs of each branch. |
