1. FLIP FLOPS

2. Types of Flip flops There are 4 mainly types of flipflop
1. SR flip flop
2. JK flip flop
3. D flip flop
4. T flip flop

3. CLOCKED R-S FLIP-FLOP SYNCHRONOUS
Set
Reset S R Q FF
Clock
CLK
SYNCHRONOUS
Clock signal determines exact time at which any output can change state

4. CLOCKED R-S FLIP-FLOP Symbols: Truth Table: Clk S R Qn No change 1
Set
Reset S R Q
Normal
Comple-mentary FF
Clock
CLK
Truth Table:
Clk S R Qn
No change 1
Race

5. POSITIVE EDGE TRIGGERED
R-S FLIP-FLOP
TIMING DIAGRAMS

6. NEGATIVE EDGE TRIGGERED
R-S FLIP-FLOP

8. D Flip-Flop
clk D
Qn+1 1

9. J-k latch E S R Qn 1 No change Toggle Race around condition J Q
No change
Toggle
Race around condition

10. Race around condition
This condition occur when j=k=1 i.e when the latch is in toggle mode.
This can be avoided by
Using edge triggering J-k flip-flop
Using master slave flip-flop

11. J-K flip-flop
Clk J k Qn
No change 1
Toggle

12. Master slave flip-flop
Clk j k Qn
No change 1
Toggle

13. T flip flop
clk T Q
comments
No change 1
toggle