| 摘要 |
PROBLEM TO BE SOLVED: To provide a connection detecting jack which can detect whether a pin plug is connected or not without increasing the cost. SOLUTION: An electrode of a pin jack 1 is divided into a first separation electrode and a second separation electrode by an insulation material. A contact terminal formed at the inside of the insertion opening of the pin jack 1 is connected to a signal processing part 3. A contact terminal formed at the inside of the insertion opening of a pin jack 2 is connected to a connection point of the pin jack 1 and the signal processing part 3. A second separation electrode of the pin jack 1 is grounded, and the first separation electrode is connected to the output side of an LED 4. The input side of the LED 4 is connected to one end of a resistor 5. An electric power Vcc is impressed between the other end of the resistor 5 and ground. When the pin plug is connected, the first electrode 2 and the second electrode 3 are connected through the electrode of the pin plug, and a light emitting diode is lighted. COPYRIGHT: (C)2003,JPO |
