Can someone help me please, i am new to this

Discussion in 'General Electronics Chat' started by highhoops, Nov 12, 2008.

  1. highhoops

    Thread Starter Member

    Nov 12, 2008
    a) a combinational logic device
    b) a sequential logic device

    Can someone please explain to me what are the operational differences between the two ? oh yeah and one more thing ,

    what is a tri state device ?
  2. scubasteve_911

    Senior Member

    Dec 27, 2007
    Combinational logic: many gates tied together, current output depends only on current input
    Sequential logic: composed of combinational logic, but has memory; thus, outputs depend on previous inputs. Can be split into moore or mealy machines, Moore is when it depends on the current state (not current input), and Mealy is when it depends on current state and current input.

    Tristate means there are three states, typically, low, high, and hi-Z

  3. Wendy


    Mar 24, 2008
    The hi-Z state output allows a logic device to switch itself out of a circuit, which allows it to share a buss (as in a computer buss) with other devices.