| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage measurement circuit for observing an AC voltage and a DC voltage of a high power output circuit in the field of power electronics, capable of performing detection from a DC voltage with a simple configuration while reducing the value of a required power source voltage and the number of components. ! SOLUTION: A voltage measurement circuit 100 includes a differential amplifier 1 that differentially outputs a voltage symmetrically centering around a unique common voltage from two output terminals to an input signal, and an operational amplifier 5 connected with a subsequent stage to the differential amplifier 1. Three resistors comprising at least a first resistor 2, a second resistor 3, and a third resistor 4 are star-connected with a positive polarity output terminal VoutP and a negative polarity output terminal VoutN of the differential amplifier 1, and an output side reference potential GND, respectively. A voltage between the center of the star connection and t |
