Patent ID: 6825577
Filing Date: 2004-11-30
Classification: H02J

Abstract:
A circuit for coupling power from a primary DC power source or an auxiliary DC power source to a telecommunication device through a power supply path having first and second nodes therefore and containing a circuit interruption device, comprising:first and second power supply connection terminals adapted to be coupled to said primary DC power source and said DC auxiliary power source and operatively connected to respective first and second nodes; and a power supply interface circuit coupled between said first and second power supply connection terminals and said first and second nodes of said power supply path, and being configured to prevent inadvertent miswiring of said power supply connection terminals to wrong polarity voltages of either of said primary or auxiliary DC power sources from triggering the operation of said circuit interruption device, said power supply interface circuit comprising first and second sets of diodes respectively connected between said first and second power supply connection terminals and respective first and second nodes of said power supply path, so as to be forward conducting for only a proper polarity connection of its associated power supply connection terminal to a respective power source, but preventing said circuit interruption device from being triggered in the event of an improper proper polarity connection of its associated power supply connection terminal to a respective power source, wherein a first diode of the first set of diodes has its anode connected to a relatively positive power source terminal and its cathode connected to the first node and a second diode has its cathode connected to a negative power source terminal and its anode connected to the second node, and a first diode in the second set of diodes has its anode connected to the positive power source terminal and its cathode connected to the first node, while the second diode in the second set has its cathode connected to the negative power source terminal and its anode connected to the second node.