| 摘要 |
PROBLEM TO BE SOLVED: To obtain a comparator circuit with an excellent hysteresis characteristic and easily used. SOLUTION: The comparator circuit is provided with a comparison section 10 that compares an input signal Vin with a reference voltage Vref to produce an output signal Vout and with a resistance voltage division section 20 that receives an output signal Vout the comparator section output. The voltage division signal is fed back to the reference voltage Vref to provide a hysteresis characteristic to the comparator circuit. In this case, The comparator circuit is provided with a changeover circuit 30 that receives 1st and 2nd constant voltages (41, 42) and selectively outputs either of them in response to the output signal Vout from the comparator section output. The resistance voltage division section 20 receives an output signal Vs of the changeover circuit in place of the output signal Vout from the comparison section. Since a feedback signal is generated on the basis of a constant voltage and a system utilizing the resistance division system and the output of a comparator section can be maintained, effect of power fluctuation is avoided, the security of precision is easy and bind of the internal structure of the comparator section is avoided.
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