Provide the correct bill of materials for a given configuration for a given build, with component locations and rotation, and they will assemble it appropriately. They might care a little bit if the pads are too big or small, as inappropriately sized pads may lead to poor solder joints, but if you follow their Design For Manufacturing (DFM) rules then there shouldn't be an issue. The RabbitFLEX product http://www.rabbitsemiconductor.com/products/RabbitFLEX/largeView.shtml is very interesting in this respect - if you get a chance to see one up close, do so. Each I/O is individually configurable by the end user during the ordering process, and based on what is chosen different components are installed in small cells. A given pad may accept one end of a resistor in one orientation, a transistor in another orientation, etc. I'm sure they've got a patent on some aspects of this that shows this close up with placement examples, but I can't find it at the moment. At any rate, your assembly house should not even blink at it. Just make sure your BOM is correct. -Adam On 6/8/07, PicDude wrote: > Hey all, > > Optimizing a really tight circuit and being able to drop even one 0805 would > be a noticeable relief. The board is setup for various configurations > (circuit variations). In one part of the circuit, one configuration requires > a SOT-23 voltage reference (such as LM4040) and another configuration > requires an 0805 resistor. But never both. Actually, pins 2 and 3 of the > SOT-23 (the two pins that are on the same side of the SOT-23 package) are the > same signals that are on both ends of the 0805 resistor, and I can actually > fit the 0805 on the SOT-23 pin 2 and pin 3 pads. Great, I can drop the 0805! > > But how do I handle this when I pass the board to a CM? Will they willingly > accept this placement, or throw it back as non-standard? What if I overlap > these two components on the board layout? Ignoring layout-software > warnings/errors, is this acceptable practice? Final option is to create a > special component that I define are being able to hold an SOT-23 or 0805, but > not sure if this is enough to appease the board houses. > > Cheers, > -Neil. > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Moving in southeast Michigan? Buy my house: http://ubasics.com/house/ Interested in electronics? Check out the projects at http://ubasics.com Building your own house? Check out http://ubasics.com/home/ -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist