Not using IC Sockets: sinful?

Hey everyone,

I have a couple 8 pin ICs (MSGEQ7s) and I was wondering if I could just solder them directly to a pcb without the need to use a socket that just takes up space. Is this ok or will the heat from the iron damage the IC? In the data sheet there's a "storage temperature" rating that goes up to ~300F whereas my iron is 350F, but surely just soldering for a couple seconds on each pin won't risk permanently damaging the IC, right? Or am I way out of line?

Thanks

You can solder parts right to a board without damaging them.

Storage temperature is not the same as soldering temperature, which is missing from the data sheet.

if I could just solder them directly to a pcb

Yes you can.

If there's no concern about removing or replacing them in the future, soldering would actually be better. The connections will be improved, and perhaps a tiny bit less stray capacitance, which is probably a nit at the frequencies we usually deal with here.

In commercial equipment. soldering ICs directly on to PCBs is the norm, except for a few high-value parts such as the processor chips in PCs.

Thing is if you use a socket you can remove the chip which is useful sometimes in fault finding and also when you want to "borrow" a chip for another project.

sciguy77:
Hey everyone,

I have a couple 8 pin ICs (MSGEQ7s) and I was wondering if I could just solder them directly to a pcb without the need to use a socket that just takes up space. Is this ok or will the heat from the iron damage the IC? In the data sheet there's a "storage temperature" rating that goes up to ~300F whereas my iron is 350F, but surely just soldering for a couple seconds on each pin won't risk permanently damaging the IC, right? Or am I way out of line?

They should be fine if you're nimble with the iron and let it cool down a bit between pins.

Clip a bulldog clip against the top of the pins on the IC, that will sink some of the heat away from the silicon and buy you several extra seconds of soldering time.

sciguy77:
Hey everyone,

I have a couple 8 pin ICs (MSGEQ7s) and I was wondering if I could just solder them directly to a pcb without the need to use a socket that just takes up space. Is this ok or will the heat from the iron damage the IC? In the data sheet there's a "storage temperature" rating that goes up to ~300F whereas my iron is 350F, but surely just soldering for a couple seconds on each pin won't risk permanently damaging the IC, right? Or am I way out of line?

Thanks

Your iron is far too cold. Iron must be hot (300C, 600F) or it will take too long to melt the solder (taking too long is more likely
to cause heat damage). The leads you solder too are not directly connected to the silicon chip, there are tiny thin gold wires
that do that, and it takes some time for heat to flow along them and overheat the silicon. Keep soldering time to a couple of
seconds per joint and you will be fine.

Perhaps you meant your iron was 350C (which is also fine).

MarkT:
The leads you solder too are not directly connected to the silicon chip, there are tiny thin gold wires
that do that, and it takes some time for heat to flow along them and overheat the silicon. Keep soldering time to a couple of
seconds per joint and you will be fine.

It's also a good idea not to solder adjacent pins in succession. Alternate between opposite sides of the chip so it has less chance of creating hotspots. You can also do all the even-number pins followed by all the odd-number pins if you want to.... :slight_smile:

I love sockets and buy them by the hundreds at taydaelectronics.com but I have had a few ones where the IC loosened up on me. Everyone says it's more reliable not to use sockets at all. I like them because I can move the ICs around (which probably contributes to the socket loosening up!)

Not using IC Sockets: sinful?

The typical question is the other way around: whether it is sinful to use sockets.