REFERENCE VOLTAGE GENERATION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a reference voltage generation circuit easy to be integrated, hardly influenced by noise, and having small fluctuation of output voltage by fluctuation of power supply voltage. SOLUTION: In this reference voltage generation circuit, a basic configuration is formed by a buffer amplifier 21 and a resistance element 22 without using a bandgap regulator so as not to come under the conventional influence of the noise of the bandgap regulator. The reference voltage generation circuit has: comparators 23, 24 comparing input voltage of the buffer amplifier 21 and output voltage of the bandgap regulator 10; and a control circuit 25 variably controlling a resistance value of the resistance element 22 according to a comparison signal thereof. Thereby, even if the output voltage Voutof the buffer amplifier 21 temporarily fluctuates according to the fluctuation of the power supply voltage VDD, the output voltage Voutof the buffer amplifier 21 returns inside a desired voltage range and converges by the variable control of the resistance value. COPYRIGHT: (C)2008,JPO&INPIT