| 摘要 |
PURPOSE: A power supply voltage level detection unit is provided, which detects a stable power supply voltage level by responding to a temperature variation insensitively. CONSTITUTION: A reference voltage generation unit(41) is constituted between a power supply stage and a ground voltage stage, and generates a reference voltage varying insensitively to a temperature characteristics and voltage variation. A voltage follower(43) responds insensitively to the temperature variation, and is constituted between the power supply stage and the ground voltage stage, and outputs a power supply voltage(VDD) with a constant ratio by receiving the reference voltage. A logic disables the reference voltage generation unit during a power saving mode. And a differential amplifier(42) detects a specific voltage level by comparing the reference voltage of the reference voltage generation unit with an output voltage of the voltage follower.
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