发明名称 Light emitting device and drive IC of portable telephone
摘要 The invention provides a light emitting device of a portable telephone, for stabilizing the brightness and color tone of the display, which operates by a power of a battery together with a communication circuit, includes plural light emitting elements of which light emission colors are different, which are driven individually by a pulse width modulation method. It also includes a voltage boosting circuit having a smoothing circuit connected to an output side thereof, whose output is supplied to the light emitting elements. Thus, by raising and stabilizing the battery voltage and supplying it to the light emitting elements, the light emitting elements are driven with a margin, and they are also blocked from an influence of the fluctuations of the battery voltage.
申请公布号 US2002047642(A1) 申请公布日期 2002.04.25
申请号 US20010968775 申请日期 2001.10.03
申请人 ROHM CO., LTD. 发明人 MIYAGAWA SHOZO
分类号 H01L33/00;H04M1/00;H04M1/02;H04M1/22;H04M1/725;H04Q7/38;H04W88/02;H05B33/08;(IPC1-7):G05F1/00 主分类号 H01L33/00
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