Once I thought that 2 parts per square inch was dense. This is 20.
Now that it's placed, I need to route it. Analog stuff tends to be local, lots of short traces, easy to route.
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
My metric was always the percentage of the board covered with components.If that got above 65% the board was going to be hard to route. There were all sort of cases where it got to be difficult to route for other reasons, but the rule sort of survived surface mount components even though they were lot smaller than their through-the-board predecessors.
Being able to put components on both sides of the board might have helped, but while I worked on jobs where this was a theoretical possibility, production really didn't like doing that.
Not exactly informative.
Byte- and word-wide buses do tend to be nasty. It they are fast and need to act like transmission lines, they get a whole lot nastier.
On one occasion I narrowed a track from 50R to 75R in the immediate vicinity of a pin to compensate the capacitative load presented by the pin, but it was fast clock line rather than part of a bus.
-- ' Bill Sloman, Sydney
Nice big ones, though. That makes life easier.
Sometimes. ;)
My stuff tends to have "everything connected to everything, with traces that all have to be short!" or so my layout colleagues would opine.
Cheers
Phil Hobbs
I does help, in fast circuits, to put every part very close to every other part.
My board is routed now. It helps to be able to change the schematic to tweak the routing.
I wonder if AI will ever be able to design and layout complex, fast, mixed-mode stuff. Maybe next century.
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
Put the caps on the bottom. Was doing this 25 years ago.
Cheers
but then you have to do double sided assembly and via take op space too
I avoided that, to make manufacturing easier. We'll only have 30 mils gap between the bottom of this board and the host motherboard.
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
My manufacturing people don't violently object to parts on both sides, but it does need two solder paste stencils and two passes through the line.
Bypass caps usually have vias anyhow.
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
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