| 摘要 |
PROBLEM TO BE SOLVED: To provide an electromagnetic valve drive unit which can reduce breakdown strength as a capacitor needs. SOLUTION: A terminal on the negative side of a capacitor 31 is connected to a terminal on the positive side of a battery 11, and a terminal on the positive side thereof is connected to the output terminal side of a DC-DC converter 20, so that a voltage obtained by subtracting the voltage of the battery 11 from the output voltage of the DC-DC converter 20 is applied between both terminals of the capacitor 31. In addition, since the terminal on the negative side of the capacitor 31 is connected to the terminal on the positive side of the battery 11, the positive side of the battery 11 becomes a reference terminal. Even if a load dump surge voltage is applied to a circuit, it is hard to be applied to the capacitor 31. Therefore, the breakdown strength of the capacitor 31 can be reduced to a voltage obtained by subtracting the voltage of the battery 11 from the output voltage of the DC-DC converter 20. As a result, an inexpensive capacitor can be used as the capacitor 31 with reduced breakdown strength, and the cost of parts can be also reduced.
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