Getting SMT Stuff Made

skrasms · Joined: Feb 21, 2008 Posts: 121 Location: Portland, OR

This is a little off-topic, but my application is in using programmable logic and microprocessors in audio designs.

There are some circuits I would really like to build, but they involve parts that I absolutely cannot solder myself (BGA, for example). What are the options for paying a company to do this?

I am expecting it to be very expensive; the only way I can think of off hand is to go through Gold Phoenix for SMT builds. From what I understand, that means paying $200 to get a stencil made for the circuit plus another $150 minimum order in assembly.

Are there other options?

State Machine · Posted: Sat Nov 01, 2008 11:14 am Post subject:

Unless you have a large quantity, then the big companies are not an option. Another option is to just use components you know you can solder and stay away from BGA's altogether. If you must use BGA's, maybe a forum member, and not a big company, can offer a hand if they have the skills and equipment. Keep in mind that large BGA's are harder to re flow than other SMT devices and requires the right thermal profile based on the size of the chip and other factors. Inspection is usually done using X-Ray gear unless you wing it and see if things work when you power up. Not good. The bottom line, BGA's should be done professionally by personnel who have the right equipment to do the job reliably. Packages like QFP's, LCC's, and DIP SO devices, they are much more manageable and with practice, you can get good at soldering these types of devices in your lab.

Another route is this, you get a prefabricated development board with the devices already soldered in place, like an FPGA development board for example, or an ARM Core logic board, then build your circuit around this core logic using your PCB and interconnect. The BGA devices will already be soldered and you save yourself the hassel. There are many MCU and processor modules that are of very small form factor that are pre-built as well.

I hope these few ideas help.

Bill

skrasms · Joined: Feb 21, 2008 Posts: 121 Location: Portland, OR

State Machine · Posted: Sat Nov 01, 2008 1:12 pm Post subject:

I agree, don't give up. My advice was aimed at steering you in a good direction Very Happy

I saw those links for posted and they seem like a viable option Very Happy

For prototyping adapters, I usually purchase these and they are very good quality at reasonable price:

http://www.beldynsys.com/kits.htm

Chat more on prototyping ............
I will take a picture of an examples using these adapters later this weekend

Bill

skrasms · Joined: Feb 21, 2008 Posts: 121 Location: Portland, OR

State Machine · Posted: Tue Dec 23, 2008 6:39 am Post subject:

skrasms · Joined: Feb 21, 2008 Posts: 121 Location: Portland, OR

urbanscallywag · Joined: Nov 30, 2007 Posts: 317 Location: sometimes

Is your problem in prototyping or manufacturing?

I've made my own SMT prototyping boards using ExpressPCB's 3 for $51 prototyping service. It ended up being much cheaper than commercial alternatives. I would like to try PCBCart to do the same thing (but they will have a much longer lead time, ExpressPCB is 3 days to your door).

For manufacturing try looking for a local small outfit to do it. A friend of mine did this recently, it was cheaper than we expected.

skrasms · Joined: Feb 21, 2008 Posts: 121 Location: Portland, OR

urbanscallywag · Joined: Nov 30, 2007 Posts: 317 Location: sometimes

Ah, BGA.

The local guy says he can do BGA but he doesn't have an X-ray to inspect the joints. We were thinking to have a lot of test points to verify a fraction of the pins using LED or a logic analyzer and a generated test.

Other than that try looking at the DIY methods using hotplates or hot air or toast ovens. Start with something low cost and easy to verify (CPLD might be a good choice) and develop a method, then work on more expensive parts.

urbanscallywag · Joined: Nov 30, 2007 Posts: 317 Location: sometimes

I forgot about SchmartBoard. They have a funny ad around with a child soldering SMT stuff with their boards.

http://www.schmartboard.com/index.asp?page=products_bga

One problem with BGA is the high density requires a board with many layers. In some cases you can't beat the complete demo board's price just for the PCB. The BeagleBoard is an example, I think the OMAP processor uses the densest BGA package there is which requires a via under every pad!

http://beagleboard.org/