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Flip flop

To make an operable circuit, a bistable element must be provided with output leads so that its state can be exploited by the remainder of the circuit. Additionally, there must be some mechanism to force it into a known state, which includes inducing it to change states. Rather than making the designer keep track of the state of the flip flop, the most elegant versions do this internally, automatically exchanging states upon the receipt of a triggering signal.

The following design incorporates a NOR gate; a single electron (arriving in the correct phase of the six phase clock), acting as a TRUE pulse, will force one or the other state, according to its entry point. The flip flop actually requires the TRUE signal for two cycles, which is arranged internally by pulse doublers.

An additional detail, not shown, would be to restrict the output stream to a single pulse. In that form the units could be cascaded to form a counter, the style of the output then being consistent with the input.

 
Figure: NOR gated FLIP FLOP

Starting from the indications shown here, any standard textbook on circuit design can be used to build up much more elaborate circuits.



Harold V. McIntosh
E-mail:mcintosh@servidor.unam.mx