BGA Rework/Prototype Placement Anyone?

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where I work we have inhouse facilities for exactly that type of work, the BGAs are not a pain at all if you have the vapor phase thing :)

and yes we do populate the new to be tested boards step by step.. to make sure the power supply doesnt blow it all appart

we are not in Canada, but postal services are fast todays :)

a plain rework station is not much good (if you main hot air station), you really need a vapor phase

also if you are doing BGAs with 0.5mm pitch then its getting more complicated to get them placed correctly, for 0.8mm it is ok to just manually place, it works also without solder being applied

0.5mm to my knowledge will not solder without extra solder being applied or needs some higher temperatures than the normal stuff, at least we have not succeeded in soldering them without paste, they just did not stick at all, well the BGA was PBfree and we had too low temperatur medium

I think there are plans here to offer the SMT services more widely (not only for inhouse needs) so we might be able to help

Antti

Circuit Centre Inc.

We get BGA placed for 75$ a chip/board (Canadian) and they are located in Scarborough (East of Toronto). They have great customer service, and care about the little guys.

Hope this helps,

Jason

We have a product coming to assist in this area. Based on Spartan-3 in FG456 it consists of a PGA style board with the Spartan-3 in the middle. This module is aimed at hobby or small run board builders that don't want the setup charges of BGA lines.

Currently sitting about 5th in our planned product release schedule it can be brought forward it we get a lot of potential demand. So let us know if you might want this product.

John Adair Enterpoint Ltd. - Home of Broaddown2. The Ultimate Spartan3 Development Board.

Sounds like a really good idea - having started playing with the S3 devkit I keep having ideas of other fun, low-volume or 1-off things that I could use an FPGA for if it were more easily connect-to-able.

Do you have a rough spec yet ? Number of pins, size, price etc. ?

You may have already thought of some/all of these, but a few suggestions...

Would be nice if the pinout is arranged such that you can easily trade off required number of layers needed on the host PCB against pins used, e.g useable on a 2-layer PCB if you don't need a lot of IO pins.

Having a power connector on the board would be useful, to reduce the amount of big tracks you'd need (and allow a 2-layer host PCB for less demanding applications). Perhaps have JTAG and power connection pins along an edge with some perforations, so that can be snapped off if you want minimum module size, or left on to make it easier to use with simpler host boards.

1.5 and 2.5V regulators on board ?

Any chance the footprint can be the same as one of the various PC CPUs, so sockets can be found cheaply ?

Probably don't need seperately accessible connections to all of the IO bank supplies, but at least one seperately connectable bank would be nice for when you want a few 'odd' standards that need a different supply, e.g. lvds. Maybe have some solder-bridge type link options for this?

Footprint for a user-fittable SMD oscillator module or two so high-speed clocks can stay on the module.

Very early days at the moment on this one but probably looking at before tax price of about £30 ($50) for something like a XC3S1500. Generally we would be aiming to keep the cost down as one of the principal markets would be hobby electronics. One of the debates we are having is what to add in addition to the FPGA. Mainly this revolves arround fitting regulators for Vccint and Vccaux. Having a straight 3V3 drop-in solution is nice for the market but the more we add the more the cost and where do you stop.

The I/O count as yet is not settled but we are likely to using the FG456 package to keep it common with our other products. It does add a bit to cost but the substantially better SSO performance, over something like the PQ208 package, is worth having even if the PCB limitations reduce the benefit. Not all the I/O is likely to available but wait and see how well we do. Whatever we do it will be 0.1 inch pitch pin-out so you can even fit it to stripboard (do I hear a few people shuddering).

Adding more than the above starts to look like a development board and we are going to cover this very low end market with our next board release once the dust has settled on our MINI-CAN launch. The next board will incorporate some very low cost design techiques and will give us a lot of info on what we could get away with on the PGA module. We are aiming at a 4-layer approach on this board to reduce the cost but keep most of the performance. Our current MINI-CAN is 8 layer and Broaddown2 is 10 layer so you can make your own guess on the price point of the new board.

John Adair Enterpoint Ltd. - Home of Broaddown2. The Ultimate Spartan3 Development Board.