AC driver having three power supply voltages including an internally generated voltage

摘要

PCT No. PCT/JP95/00270 Sec. 371 Date Oct. 20, 1995 Sec. 102(e) Date Oct. 20, 1995 PCT Filed Feb. 23, 1995 PCT Pub. No. WO95/23359 PCT Pub. Date Aug. 31, 1995The present invention relates to an improvement in an EL driver including a second power supply voltage producer for producing second supply voltage for use in driving an EL lamp using a battery serving as a first power source, a third supply voltage producer for producing third supply voltage that is higher than the first supply voltage and lower than the second supply voltage, and a driving signal supplier for supplying an AC driving signal to an EL driving means when driven by the third supply voltage. The level of the AC driving signal is increased in two steps. The EL driver semiconductor device characteristic of the high-voltage efficiency and high threshold voltage can therefore be driven by low voltage.