An analog to digital converter circuit includes encoder circuitry which employs a dummy bit line to derive timing signals employed in establishing stable, valid output digital signal information. For almost all binary codes of interest, the dummy bit line employed may actually comprise a portion of an otherwise unused bit line. The present invention is also distinguished in that it employs a clocked regenerative bit line sustainer circuit driven by dummy bit line derived timing signals. Additionally, the present invention also preferably employs a folded antiparallel architecture in which the bit lines are disposed in a generally U-shaped surrounding the parallel segments along their outer edges.