6 - Digital Circuits Review

ucla | CS M151B | 2024-01-25 17:33

Table of Contents

Combinational Circuits

  • combination of logical gates, output based on input only

    • Muxes

  • Muxes

    • Sequential Circuits

  • output based on input AND clock (usually only on posedge of clk) or inputs AND

    • D Flip-Flops

  • used to implement registers and for timing resolution
  • e.g. when combinational logic is LARGE, use register in between to mitigate

    • FSMs

  • states are based on previous state and inputs
  • e.g. 111 sequence detector

    • Mealy Machine

  • outputs based on state AND input
  • this can help us represent many states with fewer overaall states bc we now depend on inputs as well
  • However, if the input has a large delay, it may delay the output further

    Moore Machine

  • output only based on state (NS)
  • allow us to not lose the signal strength or the output since output is only based on the state which is sent by the flip-lop (which sends the voltage as a fresh/stronger signal)