<s>
Metal	B-Algorithm
electrode	I-Algorithm
leadless	I-Algorithm
face	I-Algorithm
(	O
MELF	B-Algorithm
)	O
is	O
a	O
type	O
of	O
leadless	O
cylindrical	O
electronic	O
surface	O
mount	O
device	O
that	O
is	O
metallized	O
at	O
its	O
ends	O
.	O
</s>
<s>
MELF	B-Algorithm
devices	O
are	O
usually	O
diodes	O
and	O
resistors	O
.	O
</s>
<s>
The	O
EN	O
140401-803	O
and	O
JEDEC	O
DO-213	B-Algorithm
standards	O
describe	O
multiple	O
MELF	B-Algorithm
components	O
.	O
</s>
<s>
Additionally	O
,	O
MELF	B-Algorithm
components	O
are	O
sometimes	O
called	O
a	O
"	O
roll	O
away	O
"	O
package	O
.	O
</s>
<s>
If	O
the	O
MELF	B-Algorithm
components	O
are	O
placed	O
into	O
the	O
solder	O
paste	O
with	O
enough	O
pressure	O
,	O
then	O
this	O
problem	O
can	O
be	O
minimized	O
.	O
</s>
<s>
Care	O
must	O
be	O
taken	O
with	O
glass	O
diodes	O
which	O
are	O
less	O
mechanically	O
robust	O
than	O
resistors	O
and	O
other	O
MELF	B-Algorithm
components	O
.	O
</s>
<s>
Also	O
,	O
when	O
building	O
up	O
PCBs	O
via	O
manual	O
assembly	O
using	O
tweezers	O
(	O
e.g.	O
,	O
for	O
prototyping	O
)	O
then	O
the	O
pressure	O
at	O
the	O
end	O
of	O
tweezers	O
can	O
often	O
cause	O
a	O
MELF	B-Algorithm
component	O
to	O
slip	O
and	O
shoot	O
out	O
the	O
ends	O
,	O
thereby	O
making	O
their	O
placement	O
more	O
difficult	O
,	O
compared	O
to	O
other	O
flat	O
component	O
packages	O
.	O
</s>
<s>
Another	O
reason	O
for	O
the	O
nickname	O
of	O
MELF	B-Algorithm
components	O
is	O
that	O
most	O
production	O
engineers	O
do	O
not	O
like	O
to	O
use	O
MELF	B-Algorithm
nozzles	O
on	O
a	O
SMT	O
pick-and-place	O
machine	O
.	O
</s>
<s>
For	O
them	O
it	O
is	O
waste	O
of	O
time	O
to	O
change	O
from	O
flat	O
nozzles	O
to	O
MELF	B-Algorithm
nozzles	O
.	O
</s>
<s>
For	O
MICRO-MELF	O
and	O
MINI-MELF	O
most	O
SMD	O
placers	O
are	O
able	O
to	O
use	O
flat	O
chip	O
nozzles	O
if	O
the	O
vacuum	O
is	O
high	O
enough	O
;	O
i.e.	O
,	O
higher	O
than	O
for	O
flat	O
chip	O
components	O
.	O
</s>
<s>
For	O
MELFs	O
with	O
the	O
case	O
size	O
of	O
0207	O
or	O
less	O
,	O
it	O
is	O
recommended	O
to	O
use	O
the	O
original	O
MELF	B-Algorithm
nozzle	O
supplied	O
with	O
the	O
SMT	O
machine	O
.	O
</s>
<s>
SQ	O
MELF	B-Algorithm
,	O
QuadroMELF	O
and	O
B-MELF	O
)	O
.	O
</s>
<s>
These	O
handling	O
difficulties	O
prompted	O
development	O
of	O
alternative	O
SMT	O
packages	O
for	O
common	O
MELF	B-Algorithm
components	O
(	O
like	O
diodes	O
)	O
where	O
the	O
power	O
handling	O
capability	O
needed	O
to	O
be	O
similar	O
to	O
MELF	B-Algorithm
components	O
(	O
superior	O
to	O
low-power	O
0805/0603	O
,	O
etc	O
.	O
</s>
<s>
Despite	O
their	O
handling	O
difficulties	O
,	O
and	O
in	O
the	O
particular	O
case	O
of	O
MELF	B-Algorithm
resistors	O
,	O
they	O
are	O
still	O
widely	O
used	O
in	O
high-reliability	O
and	O
precision	O
applications	O
where	O
their	O
predictable	O
characteristics	O
(	O
e.g.	O
,	O
low	O
failure	O
rate	O
with	O
well-defined	O
failure	O
modes	O
)	O
as	O
well	O
as	O
their	O
higher	O
performance	O
in	O
terms	O
of	O
accuracy	O
,	O
long-term	O
stability	O
,	O
moisture	O
resistance	O
,	O
high-temperature	O
operation	O
far	O
outweigh	O
their	O
disadvantages	O
.	O
</s>
