| 摘要 |
PURPOSE:To effectively inspect whether a capacitor having smaller electrostatic capacitance is electrically connected or not. CONSTITUTION:A ceramic capacitor 3 connected in parallel with an electrolytic capacitor 2 has smaller electrostatic capacitance than a tolerance of that of the capacitor 2. In the case of executing an in-circuit testing method, a frequency (10MHz) at the time when an impedance of the capacitor 3 becomes smaller (substantially zero) than that of the capacitor 2, is decided, and a voltage of a half waveform having its frequency is input to an electric circuit 1. A voltage to be output from the circuit 1 is measured, and an absolute value of its output voltage is compared with a judging value. The judging value is smaller than the output voltage of the circuit 1 when only the capacitor 2 is electrically connected. It is judging that the capacitor 3 is connected only when the absolute value of the output voltage is the judged value or less. |
