| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital input device in which power consumption is suppressed, space saving is attained and temperature rise is suppressed by controlling an input current at a contact provided outside the digital input device from a current value needed to destroy an oxide film of the contact to a current value needed to fulfill a function of a digital input circuit. SOLUTION: This digital input device has first and second resistances connected to first and second contacts respectively connected parallelly to an external contact, when the external contact is closed, first current is caused to flow through the first contact and the first resistance, the first contact is switched to the second contact after a prescribed time delay, and second current whose value is smaller than a first current value is caused to flow through the second contact and the second resistance.
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