Chapter 1 : Flip Flop
1 Flip-flop &
Register
~ Latches
~ Edge-triggered
flip-flops
~ Master-slave
flip-flops
~ Flip-flop operating
characteristics
~ Flip-flop
applications
Introduction
- Logic circuit
without memory element
- Cannot remember
previous output
- Output will change
every time input change
- Latches and flip-flops are the basic single-bit
memory elements used to build sequential circuit with one or two inputs/outputs, designed
using individual logic gates and feedback loops.
nLatche – The output of the latch depends on its current inputs and on its previous output and it change of state can happen at any time when it input changes.
n Flip-Flops –The output of a flip-flop also depends on current inputs and its previous output but the change of state occurs at specific times determined by a clock input.
nLatches:
n Flip-Flops –The output of a flip-flop also depends on current inputs and its previous output but the change of state occurs at specific times determined by a clock input.
nLatches:
–S-R Latch
–Gate S-R Latch
–Gate D-Latch
nFlip-Flops:
–Edge-Triggered
Flip-Flop (S-R, J-K, D)
–Asynchronous
Inputs
–Master-Slave
Flip-Flop
–Flip-Flop
Operating Characteristics
–Flip-Flop
Applications
nType of temporary storage
device that has two stable (bi-stable) state
nSimilar to flip-flop – the
outputs are connected back to opposite inputs
nMain difference from
flip-flop is the method used for changing their statech, Gated/Enabled S-R
la
nS-R lattch and Gated D latch
