| 摘要 |
A power supply protection circuit is provided for use in a mobile satellite communication apparatus which is connected to an external power supply for driving a load circuit therein. The power supply protection circuit includes first and second relay switches which electrically connect a power supply line and common ground line, respectively, to the load circuit when the power supply is normally connected in polarity and which interrupt the power supply and common ground lines leading to the load circuit when the power supply is erroneously connected in polarity. The first and the second relay switches are controlled by a diode to be closed when the power supply is normally connected to the load circuit and to be opened when the power supply is erroneously connected to the load circuit. A resistor supplies a current level adapted to operate the first and the second relay switches and the diode. |
