US Patent 9534875 Initiator

An initiator including a housing adapted to be received in an igniter or rocket motor, at least one charge at a distal end of the housing, an electro-explosive device behind the charge for detonating the charge when subject to a voltage HV, and a pressure bulkhead behind the electro-explosive device. An electronic subsystem in the housing is connected to the electro-explosive device through the bulkhead and includes a lead for providing the voltage HV to the electro-explosive device to initiate it, and a switch in the lead which does not conduct if errant voltages are present on the lead to prevent initiation of the electro-explosive device until the correct voltage HV is present.