We are bunch of guys who are software guys, we need a Router platform
has to be developed using an existing reference design, what are the
steps involved to make prototype design, can somebody summarize the
steps involved in to make prototype design.
Basically we have to make somany changes to the existing ref. design.
that was the reason I am looking for some steps to make prototype
design.
There are a few different ways to slice this problem. I'll take a stab at
it. Hopefully others will chime in on things I've missed or whatever.
1) First, if possible, obtain the original schematic and layout and any
other design documents if possible.
2) Enumerate functionality changes that are required and or desired. You
guys should be able to take a first stab at this part, but you may want to
bring in an experienced hardware person to keep you bounded and to think
of important stuff you might overlook. For example, it is important to
capture all applicable requirements, such as board form factor, agency
listings or approvals you will need, operating environment, and so on.
Also, you have to work out how you are going to program any programmable
parts (FPGA's, ROM's and so on). That is, are you going to program the
parts before the board is assembled, or after? If after, you have to make
sure you have a plan for how to do it that is electrically sound.
Testability needs to be captured here, too.
3) Use the enumerated functionality changes to create a modified
schematic. In parallel with this, you should order samples of all the
parts to make sure you can get them. Nothing is more frustrating than
designing a complicated project around a part which can't be got in time
to meet your prototype schedule. This will also allow you to double catch
certain layout related errors.
4) When the schematic is done or nearly done, you can create a routing
requirements document.
5) Then you place the parts on the board (this is a CAD operation, not a
physical operation). Then you route the board according to the
restrictions (again, this is a CAD operation) in the routing requirements
document.
6) When the design is all routed, you can send the board data to a board
house and get boards made. Then you have to have somebody assemble the
board (i.e., solder in all the parts). You may have to supply this
somebody with programmed parts. You will certainly need to supply this
person with information about part locations and a BOM. You may need to
provide additional over-riding instructions to NOT install some
programmable parts if you plan to install them yourself, after programming
them.
7) Then you have to do board bring-up and design validation. Then the
board will probably be ready for the software guys. Depending on the
details, the software guys may have to be intimately involved in the
bring-up.
8) There are a lot of testing and quality control details to be decided
upon. This depends on how many boards you will make and who will do the
testing, and so on. Some of this may need to be discussed back in step 2.
9) Once the design is thoroughly validated, you can release to
manufacturing and move on. If problems are encountered, you may have to go
back to repeat steps 3-9 again.
--Mac
