Digital Systems: Latches and Flip-Flops

Digital Systems - Study Notes

• Latches:
  • A latch is a type of digital circuit that can be used to store a single bit of data.
  • Different types include D latch, JK latch, SR latch.
  • The image shows a D latch
  • The output follows the input, but is latched (stored) once set.
• Flip-flops:
  • Flip-flops are a type of digital circuit that can be used to store a single bit of data.
  • Flip-flops can change state on positive or negative edges of a clock signal.
  • Common types are JK, SR, D, identified by diagrams.
  • Input and output signals are shown.

Flip-Flop Inputs and States

• PRE/CLR Inputs (Flip-Flop JK):
  • These are control inputs.
  • When both PRE and CLR are high, no change in the output.
  • Asynchronous inputs.
  • The output is affected without waiting for a clock edge.

Counters (Specific Example types in list)

• Synchronous Counters:
  • Clock signals applied to every flip-flop.
  • All flip-flops change state at the same time.
• Asynchronous Counters:
  • Clocks are sequentially applied to each flip-flop.
  • State changes occur in cascade/sequential manner.
  • Diagram of flip flops and clock signals.
  • Delays are dependent on previous state and not the clock.
• Specific Examples of Counter Types (Diagram):
  • 3-bit synchronous counter.
  • 4-bit asynchronous counter.

Diagram of Timing

• Type of Device (Based on Timing Diagram):
  • The timing diagrams from the image show a counter.
  • The specific counter type is a 4-bit asynchronous counter.
  • Diagram shows the state transitions (changes) as a response to input pulses.
  • Different components in the counter and the order in which the states change.