Constant-Current Design of Tunnel-Diode Logic Circuits

Two tunnel-diode logic circuits are discussed giving "AND-OR" or "NOR" operation. Germanium coupling diodes are used to provide unilateral propagation with large fan-in, and a diode gate, giving wide tolerance on the voltage parameters of the tunnel diode, is described. A fan-in of five, fan-out of three, is obtained with practical tolerances using the "AND-OR" circuitry.