| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic volume circuit where defects of a plurality of transistors(TRs) being components of a switch circuit can be all detected. SOLUTION: A plurality of switch circuits SWn are respectively connected between each connection node of resistors and an output terminal. Each switch circuit SWn comprises a 1st conductivity type 1st TR1 and a 2nd conductivity type 2nd TR2. A logic circuit 12 selects the TR1 or 2. The logic circuit 12 receives a 1st selection signal to select the switch circuit, a 2nd selection signal to select the 1st TR and a 3rd selection signal to select the 2nd TR. In a test, the logic circuit 12 selects either of the 1st and 2nd TRs depending on the reception of the 1st, 2nd and 3rd selection signals.
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