Rapid-Transfer Principles for Transistor Switching Circuits

Requirements on circuit performance in high data-rate systems depend on the type of system in which the circuits are to be used. The requirements must be derived accordingly. For the type of system in which processing delay is not a limiting factor, a theoretical analysis has disclosed two basic circuit requirements: 1) minimum time dispersion in binary elements, 2) minimum time to set a flip-flop. This paper presents the salient points of the theoretical analysis and describes circuits which uniquely meet the two basic circuit requirements. Time dispersion is minimized by applying a rapidtransfer principle to current-switching requantizing circuits. These circuits completely requantize the binary elements in both time and amplitude. The time required to store a binary element in a current-switching flip-flop is reduced by operating the transistors in the active region exclusively. Serial data rates up to 250 megabits per second have been obtained using the rapid-transfer circuit in a small test system.