Abstract


Asynchronous inputs

Asynchronous inputs affect the state of the flip-flop independently of the clock.

  • When the preset (PRE), also known as direct set (SD), is HIGH, Q is immediately set to HIGH.
  • When the clear (CLR), also known as direct reset (RD), is HIGH, Q is immediately cleared to LOW.

J-K Flip-flop


  • J is basically Set, K is basically Reset. Active-high

Important

The J-K flip-flop eliminates the invalid state when both J and K are active, causing the outputs to toggle.

T Flip-flop