Solid state detonator firing circuit

Claim 1

A FIRING CIRCUIT COMPRISING: (A) A NORMALLY CONDUCTING INPUT TRANSISTOR AND AN OUTPUT SILICON CONTROL SWITCH, (B) A TIME CONSTANT CIRCUIT MEANS INTERCONNECTING SAID TRANSISTOR AND SILICON CONTROL SWITCH, (C) A VOLTAGE DIVIDER CIRCUIT MEANS CONNECTED FOR BIASING SAID CONTROL SWITCH TO CUT OFF WHILE SAID INPUT TRANSISTOR NORMALLY CONDUCTS; ALSO A SQUIB TO BE FIRED CONNECTED IN PARALLEL WITH A RESISTOR OF APPRECIABLY HIGHER RESISTANCE THAN SAID SQUIB, THIS PARALLEL COMBINATION CONNECTED TOGETHER IN SERIES WITH A FIRING CAPACITOR ACROSS SAID SILICON CONTROL SWITCH, FIG-01 (D) SAID NORMALLY CONDUCTING INPUT TRANSISTOR BEING CUT OFF DURING INTERVALS BETWEEN NEGATIVE INPUT PULSES ALLOWING SAID TIME CONSTANT CURCUIT MEANS TO CHARGE DURING SUCH PULSE INTERVALS, AND AFTER A PREDETERMINED NUMBER OF INPUT PULSES ARE APPLIED TO SAID INPUT TRANSISTOR SAID TIME CONSTANT CIRCUIT MEANS CONNECTED THERETO BEING SUFFICIENTLY CHARGED TO APPLY ITS CHARGE TO THE GATE OF SAID SILICON CONTROL SWITCH CAUSING IT IN TURN TO CONDUCT TO DISCHARGE SAID FIRING CAPACITOR THROUGH SAID PARALLEL COMBINATION OF SQUIB AND RESISTOR FOR FIRING SAID SQUIB, (E) AN AUXILIARY INPUT CIRCUIT CONNECTED FOR APPLYING A SIGNAL TO ALSO CAUSE SAID CONTROL SWITCH TO CONDUCT FOR FIRING SAID SQUIB. (F) RESET MEANS CONNECTED TO SAID CONTROL SWITCH FOR CUTTING OFF ANY CONDUCTION THEREOF CAUSED BY EXTRANEOUS RANDOM SIGNALS PRIOR TO ARMING OF SAID SQUIB.