Radiation hardened bistable logic circuit

Claim 1

A radiation hard bistable logic circuit comprising, in combination: a first pair of transistors connected in parallel and having input and output means; a second pair of transistors connected in parallel and having input and output means; the input means for each pair comprising a common input signal connection respectively for the transistors of each pair of transistors; a branch connection from the common connection for each pair of transistors to the respective transistors of each pair; a diode connected in each branch connection and oriented to block current attempting to flow from each transistor toward the diode in its branch connection thereby precluding either transistor of each pair from influencing the other transistor of each pair due to radiation affecting any transistor of each pair; said diodes of each pair of transistors being thereby connected back to back; the output means comprising a diode in circuit with each transistor with the diodes of each pair of transistors being connected together as an OR circuit in turn connecting the OR output to the common input connection of the other pair of transistors for maintaining the logic state of the pair of transistors in which one transistor is temporarily affected by radiation, whereby when one pair of transistors is in a first logic state being on, the other pair is in a second logic state being off and vice versa.