<s>
State	O
encoding	O
assigns	O
a	O
unique	O
pattern	O
of	O
ones	O
and	O
zeros	O
to	O
each	O
defined	O
state	O
of	O
a	O
finite-state	B-Architecture
machine	I-Architecture
(	O
FSM	O
)	O
.	O
</s>
<s>
Various	O
techniques	O
and	O
algorithms	O
like	O
implication	B-Application
tables	I-Application
,	O
row	O
matching	O
,	O
and	O
successive	O
partitioning	O
algorithm	O
,	O
identify	O
and	O
remove	O
equivalent	O
or	O
redundant	O
states	O
.	O
</s>
<s>
As	O
a	O
result	O
,	O
the	O
state	B-Architecture
machine	I-Architecture
is	O
already	O
“	O
decoded	O
,	O
”	O
so	O
the	O
state	O
of	O
the	O
machine	O
is	O
determined	O
simply	O
by	O
finding	O
out	O
which	O
flip-flop	O
is	O
active	O
.	O
</s>
<s>
This	O
encoding	O
technique	O
reduces	O
the	O
width	O
of	O
the	O
combinatorial	O
logic	O
and	O
,	O
as	O
a	O
result	O
,	O
the	O
state	B-Architecture
machine	I-Architecture
requires	O
fewer	O
levels	O
of	O
logic	O
between	O
registers	O
,	O
reducing	O
its	O
complexity	O
and	O
increasing	O
its	O
speed	O
.	O
</s>
<s>
In	O
Gray	B-Device
code	I-Device
,	O
also	O
known	O
as	O
reflected	O
binary	O
code	O
,	O
state	O
are	O
assigned	O
such	O
that	O
consecutive	O
state	O
codes	O
differ	O
by	O
only	O
one	O
bit	O
.	O
</s>
<s>
But	O
the	O
hamming	O
distance	O
in	O
Gray	B-Device
code	I-Device
is	O
always	O
1	O
.	O
</s>
<s>
The	O
main	O
idea	O
in	O
the	O
design	O
of	O
state	B-Application
encoding	I-Application
for	I-Application
low	I-Application
power	I-Application
is	O
to	O
minimize	O
the	O
Hamming	O
distance	O
of	O
the	O
most	O
probable	O
state	O
transitions	O
,	O
which	O
reduces	O
switching	O
activity	O
.	O
</s>
<s>
For	O
counters	O
,	O
Gray	B-Device
coding	I-Device
gives	O
minimum	O
switching	O
activity	O
,	O
and	O
thus	O
is	O
suitable	O
for	O
low-power	O
designs	O
.	O
</s>
<s>
Gray	B-Device
encoding	I-Device
suits	O
best	O
when	O
state	O
change	O
are	O
sequential	O
.	O
</s>
<s>
In	O
arbitrary	O
state	O
changing	O
,	O
FSM	O
Gray	B-Device
code	I-Device
fails	O
for	O
low-power	O
designs	O
.	O
</s>
