| T O P I C R E V I E W |
| mjsilva |
Posted - 05 Sep 2011 : 18:21:21
I'm new to Easy-PC, and have run into a wall. I've reduced the problem to placing a single 74HC00 IC (DIP pkg) on a PCB design, making a couple of unrouted connections between pins, and running Trace Router. Most of the connections do not get routed (maybe 1/3 get routed). I've got trace/spacing of 10/10 mils so that can't be the problem. I've tried it with and without a board outline. I didn't set up the layers, but the layers bar shows top and bottom copper and all the other layers I'd expect.
I'm at a loss here. What simple thing am I missing? |
| 4 L A T E S T R E P L I E S (Newest First) |
| Iain Wilkie |
Posted - 09 Aug 2019 : 09:14:46
A bit of advice at a professional level ..... just don't use an auto-router at all !!
Iain
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| nigelwright7557 |
Posted - 09 Aug 2019 : 08:54:23
An auto-router cant read the circuit designers mind, things like star grounding etc. So I tend to run mine and then go in and fix what I don't like.
I convert schematic to a pcb.
I then go into pcb and move components close together.
Then run net optimiser.
Then autoroute.
Fix what the auto-router did.
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| mjsilva |
Posted - 07 Sep 2011 : 05:46:18
OK, here's what I have discovered. All spacings were 10 mil except to-board spacings (using the default technology file). Board-to-trace spacing was 80 mil. When I reduced that to 50 mil the board routed. Keep in mind this is one DIP IC in the middle of a board about 4 inches on a side. 80 mil, no route, 50 mil, route. No other to-board spacings seemed to cause a problem. What's going wrong, I can't imagine.
As an aside, I'm noticing that trace route produces some pretty ugly routing in 45 degree mode. The best results seem to come from using 90 degree mode and then pulling tight all traces.
BTW, I know there's a body of opinion out there against autorouting, but darn it, I paid for it and I want it to work. |
| edrees |
Posted - 06 Sep 2011 : 09:15:11
I suspect that it's because trace router wants to run tracks in between the DIL pins. Repeat the exercise with just two axial resistors in series witheach other so there is plenty of space for the tracks. Have a look in Design Technology > Spacings. Here you may find that the track to pad spacing is too large for the DIL design. |
