choice between 0805 or 0603 ?

[Adam S]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason
is sizes below 0603 can give rise to potential problems during assembly
and sizes above 0603 are more expensive.

 

[Paul Burke]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason
is sizes below 0603 can give rise to potential problems during assembly
and sizes above 0603 are more expensive.

I suppose my stuff is in that category. I've gone to 0603 for space
reasons on a few boards, and my board stuffer finds it possible to work
with- though he prefers 0805. He screamed when I suggested 0402. He
assembles mostly by hand BTW. So I tend to use 0603 for everything new,
on the grounds that eventually we'll only have to stock one size.

 

[Jeff L]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason
is sizes below 0603 can give rise to potential problems during assembly
and sizes above 0603 are more expensive.

That is correct. 0603 is cheapest, and easier to work with then 0402 and
smaller.

 

[Christopher Ott]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason is
sizes below 0603 can give rise to potential problems during assembly and
sizes above 0603 are more expensive.

In the volumes you're using, with no space constraints, the 0805 is usually
a better solution. Yes, they are marginally more expensive, and use a little
more paste (serious considerations for large volume assembly), but the
larger parts have fewer assembly problems and will handle a little more
power. Rework is easier (therefore cheaper), and visual inspection is easier
(therefore more accurate). 0805 parts are marked with the resistance, 0603
usually are not.

Digikey shows a 5k spool of 0603 1% resistors at $36.75, and a 5k spool of
0805 1% resistors at $39.00.

Chris

 

[PeteS]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason
is sizes below 0603 can give rise to potential problems during assembly
and sizes above 0603 are more expensive.

Depends on what you need. If you have high speed signals flying about
then 0402 devices have significantly lower parasitics (and are
comparable in cost to 0603 when board space is taken into account). If
you have something where that's not an issue then 0603 is currently the
cheapest solution. That will probably change fairly soon though as 0402
parts become the 'standard' part.

Cheers

PeteS

 

[colin]

When PCB space is not a constraint and volumes are low ( <= 1000 units
year), what is the most popular SMD package size these days for passives ?
It seems high volume manufactures all go for 0603. I assume the reason is
sizes below 0603 can give rise to potential problems during assembly and
sizes above 0603 are more expensive.

0805 is most convenient size for me to use with home made pcbs.
and its still possible to read those resistor number codes.

although I have used 0603, only cos I didnt realise how small they were to
start with.

Colin =^.^=