| 摘要 |
PROBLEM TO BE SOLVED: To provide a relay device circuit which is simple and compact, for a reduced cost, wherein heating from a relay is effectively prevented. SOLUTION: The relay drive circuit is provided in which the electrification to an excitation coil 3B of a relay 3 is turned on/off by a relay drive transistor 2. Here, a current limit resistor 7 and a current switching transistor 8 are provided in parallel down stream the excitation coil 3B, and a voltage between a relay contact point part 3A and a load 6 is guided to a base terminal of the current switching transistor 8. When switching the relay 3, the current switching transistor 8 is turned on to apply the excitation coil 3 with a sufficient current while, after switching the relay 3, the current switching transistor 8 is turned off to limit the current to the excitation coil 3 with the current limit transistor 7.
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