| 摘要 |
PROBLEM TO BE SOLVED: To obtain the power source drop circuit which stably drives a circuit element, makes the current consumption in standby mode small, and reduces a DC current leak by making it possible to switch an internal source voltage generated from an external source voltage among >=3 voltage values. SOLUTION: The power source drop circuit is set to a desired internal source voltage VDDin such as a source voltage VDD for normal driving, a source voltage for a burn-in test, etc., or a standby source voltage Vstby in standby mode through logical operation wherein voltage-division level signals divided by resistances are selected by switches (Pch transistors Tr1 to Tr3) while the constant external source voltage supplied from outside is maintained without being varied and supplies the desired internal source voltage by stably driving an amplification part 4.
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