| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve detection accuracy of a state of a low side switch while reducing increase in circuit scale.SOLUTION: An ECU 11 is connected to a switch SW1 or SWn, one end of which is connected to the ground, and a DC power source 12. A CPU 21 comprises an input terminal IN to be inputted with a signal showing a detection value of a current detection circuit 22 for detecting an input current from the power source 12 and a port 1 or n with variable input impedance. Resistance Rb1 or Rbn is connected between the port 1 or n and the switch SW1 or SWn, and one end near the switch SW1 or SWn is connected to an end different from the other end connected to the power source 12 of the current detection circuit 22. The CPU 21 detects on/off states of the switch SW1 or SWn on the basis of change in input current when changing the input impedance of the port 1 or n. The control device can be applied for the ECU for instance.</p> |
