| 摘要 |
PROBLEM TO BE SOLVED: To provide a gradation display reference voltage generation circuit in which the area occupied by resistance division circuits can be made smaller and electric power consumption can be reduced and optimum gradation display voltages can be obtained respectively at the time of positive polarity driving and negative polarity driving of different characteristics and a liquid crystal drive unit using the same. SOLUTION: The first reference voltages VH0 to VH63 generated by resistors RH0 to RH64 for the positive polarity of a first ladder resistance circuit of a first reference voltage generation section LDH at the time of the positive polarity driving are outputted respectively from reference voltage output terminals T0 to T63. On the other hand, the second reference voltages VL0 to VL63 generated by resistors RL0 to RL64 for the positive polarity of a second ladder resistance circuit of a second reference voltage generation section LDL at the time of the negative polarity driving are outputted respectively from the reference voltage output terminals T0 to T63. The resistance ratios of the resistors RH0 to RH64 for the positive polarity and the resistance ratios of the resistors RL0 to RL64 for the negative polarity vary. COPYRIGHT: (C)2007,JPO&INPIT
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