This is to bring to everyone's attention two things that came up where some members might not be interested to check (although they should be ) . One is from a 65816 topic and one from the Forth section.

In the topic "I/O not in bank 0" under "Hardware," BigDumbDinosaur wrote:

I've found SOJ and SOIC to be surprisingly easy to solder. A paragraph from my post a few years ago:


Aries and other manufacturers offer adapters to make SOICs and other SMT parts able to be plugged into DIP sockets. Here's a page of Aries ones, some of which I've used: http://www.arieselec.com/products/overv ... apters.htm ; and an example:




And in the topic "6502 Forth with hardware accelerator" in the Forth section, BigEd wrote:

The other alternative is PLCCs, which can be put in sockets-- even wire-wrap sockets-- that fit into breadboards with the holes on a .1" grid. I got my McKenzie Berg PLCC wire-wrap sockets from Allied. Unfortunately Allied doesn't seem to have them anymore, nor does http://smt-adapter.biz/ . However, BigEd pointed us to a source that stocks WW PLCC sockets in many sizes: http://uk.rs-online.com/web/c/?searchTe ... ra=oss&r=t .

Here's a picture of one of my 44-pin ones:


As you can see, it's not one of those more-common monstrosities with a big PC board around the outside and all the WW pins outside the perimeter of the actual socket. It takes no more room than a non-wire-wrap PLCC socket.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I just picked up one of these boards because Fry's had them.
http://www.schmartboard.com/index.asp?page=products_so

Kind of pricey IMHO but if it works out I will be able to mount 2 chips, class D audio amplifiers ti TPA3120, on one board. Picked up some snap headers too but I haven't decided the layout I want to use yet.

Rick

I'm going to take delivery of my first SMT boards soon (From BatchPCB) shortly. A few 1206 passives, a slightly bigger diode, an SOIC-8T chip, and a couple of PTH pieces (Bulk electrolytic, high-power resistor and inductor).

The interesting part is going to be the SOIC-8T. The T means thermal pad - theres a big slug of metal on the bottom to dissipate the heat it will be producing. I've strategically placed a via right underneath, so it should be solder-able - we will just have to see whether I manage to do so without shorting the pad to the other pins!

Yes, in this case, the pad is needed; if the board is used to it's maximum specifications, 40V 1A then, since it's worst case is 80% efficiency, it could be dissipating 5W of heat. The board will be mounted to a heat sink - probably one shared by the High-brightness LEDs it's driving!

All in all, it should be interesting

The adapters take up substantially more PCB real estate than the actual part, partially defeating the advantage of small-outline components.

The 50 mil spacing on SOJ parts in itself shouldn't pose too much a problem in soldering. Where it seems most would run into trouble would be in actually getting a secure joint, due to the pins curling under the part. The problem would be in getting the solder to flow to where it is needed.

There's a U-Toobe video in which a technique for soldering a PLCC package directly to the PCB is demonstrated. As the PLCC package has J-leads, I would think the same technique should work with any SOJ part.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Above, I wrote:

I couldn't figure out how to order the 20-pin ones from the selection guide, so I Emailed them and asked. The unfortunate response was that they're not making them anymore. Milos wrote:

I haven't found any other sources. If someone else has, let us know. Otherwise, if you think you might someday want 32- or 68-pin WW PLCC sockets, better get them now! [Edit, 1/21/13: BigEd just pointed us to a source that stocks them in many sizes: http://uk.rs-online.com/web/c/?searchTe ... ra=oss&r=t ]

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Here's a couple more for ya... I used the thru-hole 44-pin PLCC socket for the 65C02, from http://smt-adapter.biz/ and planted it on wire wrap headers that were trimmed for the socket.

Here's another site I came across early on in my prototyping...

http://www.phoenixent.com/

Edit(01/03/09): Also just found this one. I needed a 28 SOJ to 28 PDIP adapter for a 10ns 8Kx8 SRAM.

http://www.ezprototypes.com/DipAdaptersMain.php

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65Org16:https://github.com/ElEctric-EyE/verilog-6502

My boards arrived from BatchPCB today. The quality is good, and I can't complain of the quantity - I ordered two and then sent me 8! Perhaps they had some issues with other designs on the panel and had to re-run it 4 times (which does seem excessive!), or perhaps they just had some spare space on the panel and used it to fill in (It's only 1 sq inch). Regardless, I now have more driver boards than I know what to do with!

I'll shortly be doing a beep-out on them, but they certainly all look good.

For timeline purposes, I placed the order on Sat 12th Dec, it was panelized on 14th Dec, and went out for fabrication that day. The boards arrived at their office, and they shipped the package on the 28th Dec, it arrived in the UK this morning. It would have likely arrived quicker if I'd ordered quicker shipping.

The turn around of 2 weeks from order to ship isn't bad for the price, particularly considering the factory was closed for much of it! I'll remember to use faster postage in future though

(Incidentally, I didn't notice how scratched the top of my subwoofer was! Oh, and that mark over the connectors? I'm going to guess thats a cat hair, since the mark doesn't exist on the board)

I know this is 100% opposite to what most people are looking to do, but it seems to me that a decent way to gain practice in soldering surface-mount components is to use traditional through-hole parts and bend the leads around the package (emulating a J-lead device) or flatten them out to emulate gull-wing devices. IIRC, the term "flat pack" dates back to the 70s where many hybrid modules were available as 100-mil pitch gull-wing unit.

What are people's thoughts on this?

(I didn't want to start a new thread because it seemed related to what's discussed here. If I'm wrong, feel free to move the message.)

The pin spacing is likely to be a problem if you're trying to practice working with SMT parts, as it's likely to make the normal drag solder method unworkable. In other words, you'd end up practicing on something that behaves rather differently.

I can't say I had a lot of experience with either flat packs or hybrid
modules in the '70s but I think all the flat packs I ever delt with then
had 50 mil spacing and the hybrid modules were all through hole with
100 mil spacing (and I don't think any of them used flat packs they
were all beam lead or flip chip or what ever they called them)

Why not just get an old surface mount board and practice on it?

eg an old motherboard or maybe a memory module.

ps: a surface mount type hybrid module would have been a blessing,
the ceramic substrate on the ones we used generally went to pieces
if the alignment of the leads and through holes wasn't absolutely
perfect.

My introduction to hybrids in the 80's was that they were basically ICs that plugged into an IC socket but they had multiple silicon chips in them, not just one as with a regular IC. The substrate was ceramic, not normal PC board, and connections to the chips were of course made with bondwires. A frequent example was high-precision A/D converters. After assembly, the cover was brazed on. Pin spacing was .100". I don't seem to be able to find a picture.

Quickly the definition of "hybrid" seemed to change to also include small SMT PC boards that plugged into other boards without necessarily looking like an IC. You can make your own that do plug into an IC socket however with edge pins from Interplex . Unfortunately even a 6502 or '22 in PQFP is too wide to go on a module that plugs into a .600"-pin spacing IC socket, which I think is what stopped us from making a 6502-pin-compatible '816 replacement when we were discussing it some time back at viewtopic.php?t=186. For applications where your hybrid doesn't have to plug into pre-existing boards and sockets, I suppose there's nothing to keep you from cutting a .600" socket and spacing the two rows farther apart, say .800" or even more, and putting more of the circuitry on the hybrid, possibly keeping all the fastest signals onboard so most pins can be used for I/O instead of buses.

I would be more attracted to making these hybrids if there were a good way to mount BGA's at home without expensive equipment. Anyone know? That would be the cat's meow. Then you could even put Cypress's new 4Mx8 SRAM onboard.

Ladies and gentlemen, I introduce you to . . . the original flatpack.

http://www.vintchip.com/FLATPACK/flatpa ... 4h00-1.JPG

Heh, is that the datecode on the bottom? Sweet...

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65Org16:https://github.com/ElEctric-EyE/verilog-6502

I got one of the PCBs assembled last night. I found the SMT passives to be quite easy; 1206 components are very manageable. 0603s are reputedly easier (in spite of being smaller); I'll have to try them next time. I'd say that the evidence corroborates that though: The SMB diode package was harder to solder; it's also noticeably bigger. Looking from the side, it's not flat; in fact, one of the pads could be said to be floating on the solder.

The chip was slightly more difficult, though largely because I did things backwards and soldered the passives first . If I'd soldered the chip down first, I'd have had more room to work with. As is, I got a few jumpers and had to use some solder braid.

It took longer than DIP parts, but that's only a lack of practice. Once used to SMT, I can easily see it being much faster, because of the lack of need to thread parts through holes and cut their leads.

Does anyone know what's going on with Jameco? For many years, they've sent me the normal catalog updates automatically, but last week I got a thing in the mail from them saying to go to www.Jameco.com/CAT10 to order a free online catalog, so I figured they want to make sure they're only sending it to people who want it. So I go to that address, and it says the page cannot be found, then re-directs me to supposedly the front page I guess, which is blank now-- nothing on it.