STEP file, which viewer?

So you do use hierarchy. ;-)

Try it with a modern uP, even something as simple as an M0.

Yup. That's why I am trying to convince Cadsoft for year. So far they don't get it how important a hierarchy is :-(

My client didn't either and the PCB house threw in a rush order for free. Like a car rental company that had to give me an all decked-out Suburban after botching my compact car reservation.

Flat sheet structures become a mess when the project is very large. AFAIR the stack of schematics for the first ultrasound machine I worked on contained over 200 sheets. That simply does not work in a flat structure.

Yes, but not discrete filter blocks. Imagine 256 of them.

Ummm yeah, right Hammond had that useless *crap* linked by Digikey, but it looks like it's all igs and stp now, with dxf for 2D. Eg.

Naturally, TE themselves have proper IGS, STP and DXF (2D) available on their website (for the part number you mentioned):

Apparently there *is* a way to export STP and IGS from 3D PDF but maybe not if you don't cross Adobe's palm with about $500 worth of silver (and only if it was created in a certain mode: U3D)- or some other expensive progrm. That kind of stuff drives me up the wall.

They're just trying to insinuate themselves into another area, and bloating their readers up with a full 3D viewer program so they can make more money. Plus they probably want to extract license fees from every MCAD company to allow them to open 3D PDF directly. SW 2013 does

Interchangable industry-standard file formats such as IGS and STP is

Best regards, Spehro Pefhany

I have done some guard traces that just ended without a pad or via. The board houses mostly seem to have software that checks for stuff like that, and they usually call us to see if it's a mistake. That's fine.

Not on my schematics!

My processor was about 40 MSI chips, on two boards, for a shipboard data logger. The next generation used a 6800.

But I don't design ICs; I put parts on boards. I can see, probe, and replace those parts, which you can't do very well on an IC. It's different.

"U1517" doesn't fit on the silk very well.

Yup, they probably target toy projects :-)

Same for the last project here. Counting 200 pages, with 10 blocks of 5 identical channels. The board is so cluttered that layout time schematic optimization is mandatory... and I'd hate mod the channel schematic 50 times in a row at each iteration...

I don't like Adobe much because of the poor quality of their reader. But I have to say that the 3D stuff works well. We exchange 3D renderings that way in a group.

Apparently few here do, either.

It only took OrCAD twenty years to get theirs working. Their solution isn't so great, either. Reference designators are still a PITA (well, they were last time I checked - haven't used OrCAD in three years).

..and guarantee that all of them are kept in sync.

You drew every transistor in the "chips"?

It not different. Just a matter of scale.

If you have more than 1000 like parts on a schematic, you're going to need four digits, in any case[*]. But you don't necessarily need four digits. I've done hierarchical schematics with three. It took a little planning but even with software as dumb as OrCAD it wasn't impossible. Though, if it weren't so dumb it would have been a lot easier. It was a *lot* easier to control than repetition, over the long haul.

Do you create them?

Best regards, Spehro Pefhany

I didn't have schematics of the chips, and I didn't design the chips.

If you use standard chips on a PCB, do you include THEIR internal schematics in your hierarchal board schematic? Why not?

I don't program PCB layouts in VHDL, and I hope I never will. My brain is more visual than verbal (almost flunked out of high school over French) so I like schematics.

I guess some board-level design has been done in a programming language, and not as a schematic. Somewhere.

There was an analog IC VHDL or Verilog or something, don't know if it's popular. I guess it's not an "RTL" if it doesn't have registers.

The densest board we've done was a VME module with about 1100 parts, stuff on both sides. Horrible. But we got by with 3-digit designators. We like reference designators, but they get dicey with dense boards and 0603 parts.

All of you need to stop your bickering and buy Multisim. It does hierarchical subsheets and all that. But each instance of a sheet is auto-generated a new (sequential, if available) set of refdes. So good luck trying to specify component names, or use multi-part components (like gates) across subsheets. Also, when you go to print, it prints off a sheet for each instance, so you can do the hierarchy, and still point to refdes so-and-so on page something-or-other. (The forward annotation netlist is flat, but you can specify groups of components to place-as-template in Ultiboard.)

Tim

I guess you missed the smiley.

Schematics are great for dataflow, not so much for control logic. You quickly get to appreciate hierarchy, though.

It is.

VHDL will accommodate analog but, no, I don't know anyone using it for analog. Analog isn't the entire world, though.

My last couple of boards are in the few hundreds of components but before that the average was ~1200, with two at 1500. I tend to use reference designators to mean something, at least in the design phase (900s being optional and debug stuff, 800s power supplies, 1000s new stuff since the last rev, etc.). Of course, that goes out the window if there are >1000 capacitors. ;-)

On the more dense boards, I sometimes have the CAD guy renumber them from side to side starting at 1 on the top and 500 on the bottom. That has its issues, too.

BTW, 0402 is the standard size, though I will use 0603s in places where changes are expected/planned. 0402s fit in nice lines next to QFPs (two 0402s resistors with a 0603 cap (resistor) across makes a nice tight filter (or pad) on a differential analog output of a DAC, for instance. We don't do 0201s, yet (and likely not in the time I expect to be there).

Not really. Orcad-SDT did the hierarchy beautifully. I still miss that software. Well, I still have the license.

The ME I work with does.