Over-voltage protective circuit

Claim 1

AN OVER-VOLTAGE PROTECTIVE CIRCUIT FOR DIRECT CURRENT POWER SUPPLIES COMPRISING A PAIR OF INPUT TERMINALS FOR CONNECTION TO A DIRECT CURRENT SUPPLY, A PAIR OF OUTPUT TERMINALS FOR CONNECTION TO A LOAD, A PASSING TRANSISTOR HAVING BASE, EMITTER, AND COLLECTOR ELECTRODES, SAID EMITTER ELECTRODE BEING CONNECTED TO ONE OF SAID PAIR OF INPUT TERMINALS, AND SAID COLLECTOR ELECTRODE BEING CONNECTED TO ONE OF SAID PAIR OF OUTPUT TERMINALS, A VOLTAGE SENSING CIRCUIT CONNECTED ACROSS SAID INPUT TERMINALS, A FIXED BIAS CIRCUIT CONNECTED BETWEEN THE EMITTER AND BASE ELECTRODES OF SAID PASSING TRANSISTOR, SAID FIXED BIAS CIRCUIT PROVIDING A BIAS TO BACK BIAS SAID PASSING TRANSISTOR, AND AN AMPLIFIER CIRCUIT HAVING AN INPUT CIRCUIT CONNECTED TO SAID SENSING CIRCUIT AND AN OUTPUT CIRCUIT CONNECTED TO SAID BASE ELECTRODE OF SAID PASSING TRANSISTOR, SAID AMPLIFIER CIRCUIT PROVIDING A CURRENT DURING THE SENSING OF NORMAL VOLTAGE AT THE INPUT TERMINALS TO OVERCOME THE BACK BIAS OF SAID PASSING TRANSISTOR PROVIDED BY SAID FIXED BIAS THEREBY FORWARD BIASING SAID PASSING TRANSISTOR, AND SAID AMPLIFIER CIRCUIT PROVIDING A REDUCED CURRENT UPON THE SENSING OF AN OVER-VOLTAGE AT SAID INPUT TERMINALS TO PERMIT SAID FIXED BIAS TO BACK BIAS SAID ELECTRODE WITH RESPECT TO SAID EMITTER ELECTRODE OF SAID PASSING TRANSISTOR THEREBY REDUCING THE CONDUCTION OF SAID PASSING TRANSISTOR.