| 摘要 |
PROBLEM TO BE SOLVED: To simplify the constitution of a current switch circuit and to constitute a current mirror circuit with single circuit by providing two differential comparators and one current mirror circuit which returns a part of the sum of the current of the current switch circuit to the output side. SOLUTION: In an absolute value detection circuit, there are provided first differential comparator, which comprises a first current switch circuit and is provided with NPN transistors Q1 to Q3, a second comparator which comprises a second current switch circuit and is provided with NPN transistors Q4 to Q6, and one current mirror circuit for returning a part of the sum of output current in the first and second current switch circuits to the output side of an absolute value detection circuit. The current mirror circuit is constituted of PNP transistors Q7 and Q8 and a resistor R6. The emitters of the transistors Q7 and Q8 are connected to a Vcc power source in parallel, the bases of the transistors Q7 and Q8 are connected to the collector of the transistor Q7 in parallel, and the collector of the transistor Q7 is connected to one of the terminals of a current source I2.
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