| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power source using a piezoelectric transformer, which enables to monitor the output of the piezoelectric transformer and to make its dimension small without adding a sophisticated circuit or the like. SOLUTION: The piezoelectric transformer 21 has input terminals 21a, 21b, an output terminal 21c and an output monitor terminal 21d. An AC power source 22 is connected between the input terminal 21a, 21b and an AC output voltage generated between the output terminal 21c and a ground line GND is supplied to a load 23. The piezoelectric transformer has the input terminals 21a, 21b on the upper face and the lower face of an input element 25 and the output terminal 21c in the front face of an output element 26. An output monitor pole 27 in a strip is formed on one face of the output element 26 at a position apart a prescribed distance from the output terminal 21c, and on this pole 27 an output monitor terminal 21d is provided. An output control of the piezoelectric transformer is made by obtaining a sufficiently low voltage comparing with the output voltage of the load as the supervisory voltage from the output monitor terminal 21d. |
