| 摘要 |
PROBLEM TO BE SOLVED: To provide an alarm sound generation circuit 10, easily detecting the bonding state between a piezoelectric buzzer A and a lead wire 30 without generating an alarm sound and a fire alarm 1 using the alarm sound generation circuit 10. SOLUTION: This alarm sound generation circuit includes a bonding part 11 bonding the lead wire 30 from a driving circuit 5 to the surface of an electrode of the piezoelectric buzzer A using soldering or the like, wherein the piezoelectric buzzer A is sounded depending upon the fluctuating voltage from the driving circuit 5 to generate alarm sound. An electric resistor R1 is bonded in a part different from the bonding part 11 between the electrodes of the piezoelectric buzzer A, thereby parallel-connecting the piezoelectric buzzer A and the electric resistor R1 to the driving circuit 5. COPYRIGHT: (C)2006,JPO&NCIPI
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