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Flip Flop ConversionjohnMarch - 1 - 2012

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For the conversion of one flip flopto another, a combinational circuit has to be designedfirst. If a ! Fli" Flo" is re#uired, the in"uts are given to the combinational circuit andthe out"ut of the combinational circuit is connected to the in"uts of the actual fli" flo".

$hus, the out"ut of the actual fli" flo" is the out"ut of the re#uired fli" flo". In this "ost,

the follo%ing fli" flo" conversions %ill be e&"lained.

SR Flip Flop to JK Flip Flop

JK Flip Flop to SR Flip Flop

SR Flip Flop to D Flip Flop

D Flip Flop to SR Flip Flop

JK Flip Flop to T Flip Flop

JK Flip Flop to D Flip Flop

D Flip Flop to JK Flip Flop

SR Flip Flop to JK Flip Flop

's told earlier, and ! %ill be given as e&ternal in"uts to ( and ). 's sho%n in the logic

diagram belo%, ( and ) %ill be the out"uts of the combinational circuit.

$he truth tables for the fli" flo" conversion are given belo%. $he "resent state isre"resented b* +" and +"1 is the ne&t state to be obtained %hen the and ! in"uts are

a""lied.

For t%o in"uts and !, there %ill be eight "ossible combinations. For each combination

of , ! and +", the corres"onding +"1 states are found. +"1 sim"l* suggests thefuture values to be obtained b* the ! fli" flo" after the value of +". $he table is then

com"leted b* %riting the values of ( and ) re#uired to get each +"1 from the

corres"onding +". $hat is, the values of ( and ) that are re#uired to change the state ofthe fli" flo" from +" to +"1 are %ritten.

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() Fli" Flo" to ! Fli" Flo" JK Flip Flop to SR Flip Flop

$his %ill be the reverse "rocess of the above e&"lained conversion. ( and ) %ill be thee&ternal in"uts to and !. 's sho%n in the logic diagram belo%, and ! %ill be the

out"uts of the combinational circuit. $hus, the values of and ! have to be obtained in

terms of (, ) and +". $he logic diagram is sho%n belo%.

' conversion table is to be %ritten using (, ), +", +"1, and !. For t%o in"uts, ( and), eight combinations are made. For each combination, the corres"onding +"1 out"uts

are found ut. $he out"uts for the combinations of (1 and )1 are not "ermitted for an

() fli" flo". $hus the out"uts are considered invalid and the and ! values are taen as/dont cares.

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! Fli" Flo" to () Fli" Flo"

SR Flip Flop to D Flip Flop

's sho%n in the figure, ( and ) are the actual in"uts of the fli" flo" and is the e&ternal

in"ut of the fli" flo". $he four combinations, the logic diagram, conversion table, and the!-ma" for ( and ) in terms of and +" are sho%n belo%.

() Fli" Flo" to Fli" Flo"

D Flip Flop to SR Flip Flop

is the actual in"ut of the fli" flo" and ( and ) are the e&ternal in"uts. 3ight "ossible

combinations are achieved from the e&ternal in"uts (, ) and +". ut, since the

combination of (1 and )1 are invalid, the values of +"1 and are considered as

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/dont cares. $he logic diagram sho%ing the conversion from to (), and the !-ma"

for in terms of (, ) and +" are sho%n belo%.

Fli" Flo" to () Fli" Flo"

JK Flip Flop to T Flip Flop

and ! are the actual in"uts of the fli" flo" and $ is taen as the e&ternal in"ut for

conversion. Four combinations are "roduced %ith $ and +". and ! are e&"ressed interms of $ and +". $he conversion table, !-ma"s, and the logic diagram are given belo%.

! Fli" Flo" to $ Fli" Flo"

JK Flip Flop to D Flip Flop

is the e&ternal in"ut and and ! are the actual in"uts of the fli" flo". and +" mae

four combinations. and ! are e&"ressed in terms of and +". $he four combination

conversion table, the !-ma"s for and ! in terms of and +", and the logic diagram

sho%ing the conversion from ! to are given belo%.

http://www.circuitstoday.com/wp-content/uploads/2012/02/JK-Flip-Flop-to-T-Flip-Flop.jpghttp://www.circuitstoday.com/wp-content/uploads/2012/02/D-Flip-Flop-to-SR-Flip-Flop.jpg

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! Fli" Flo" to Fli" Flo"

D Flip Flop to JK Flip Flop

In this conversion, is the actual in"ut to the fli" flo" and and ! are the e&ternalin"uts. , ! and +" mae eight "ossible combinations, as sho%n in the conversion table

belo%. is e&"ressed in terms of , ! and +".

$he conversion table, the !-ma" for in terms of , ! and +" and the logic diagram

sho%ing the conversion from to ! are given in the figure belo%.

Fli" Flo" to ! Fli" Flo"

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