Questions about the routing of printed circuit boards (PCBs) which involves the placement of tracks on the board. It may be performed manually, but many PCB CAD programs provide an autorouter to assist in the process.
Questions tagged [routing]
320 questions
81
votes
11 answers
Why is there such a strong preference for 45 degree angles in PCB routing?
I've always wondered this: every single modern PCB is routed at 45 degree angle increments. Why does the industry prefer this so much? Doesn't any-angle routing offer more flexibility?
One plausible theory would be that the existing tools only…
Roman Starkov
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54
votes
14 answers
Solid ground-plane vs hatched ground-plane
Recently while routing a PCB, I came across the option to fill/pour my ground plane with either solid or hatched copper. I've also noticed that the old Arduino Duemilanove also had a hatched ground plane.
What benefits does a hatched ground plane…
Vikram
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39
votes
2 answers
Purpose of "wave shaped" PCB traces
On some PCB designs, specific traces are routed in curious ways. This probably has to do with high frequency design considerations and general signal behavior that I am not familiar with.
Let's take this PCB (somewhere from the web) as an example.…
Rev
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36
votes
2 answers
What is Manhattan routing?
In an answer by The Photon he mentions 'Manhattan routing' in regards to PCB design. I haven't found a lot of relevant information about this term on the internet; therefore the question: What is Manhattan routing?
m.Alin
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33
votes
2 answers
Ground ring -- good or bad?
Here are two routings:
Which is better? On one hand, the first is bad because ground ring is one-turn coil, hence induction current will be appear. On other hand, the second is bad because potential in the opposite points of ground plane will…
user54579
31
votes
7 answers
Finding air wires in Eagle
I am almost done routing a board. However, Eagle is telling me that there is still one more wire. I have looked but I just can't seem to find it. Is there a way to make Eagle tell me where it is?
Alexis K
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30
votes
10 answers
Do you layout in mil or mm?
I have been using 10 mil trace with 10 mil spacing. The PCB vendors quote that they like traces down to 7 mil. But then I ran across a PDF showing how to fan out a QFP to get all the signals accessible. They use millimeters because the QFPs are…
Robert Deml
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24
votes
8 answers
Advice on going from rat's nest to routed PCB
Can anyone offer any useful strategies on going from a rat's nest to a routed PCB?
(I'm using Eagle and aiming to make single/double sided PCBs at home)
Drawing the schematic is fine, but when it comes to routing the tracks, it feels like…
Toby Jaffey
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18
votes
2 answers
USB signal routing - Swap data lines using vias?
I'm making my second USB design, but the D+/D- pins on the MCU (atemga16u2) aren't in the right order for the micro B connector. What's the best practice for routing these to go the right way? My current idea is to rotate the atmega 180 degrees and…
monty
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17
votes
6 answers
Anything bad to place a via on a pad?
Once I mistakenly placed a via on 0603 pad and didn't have any problem on soldering. I am routing another board now and I could save some space by placing some vias (0.3mm) on a 0603 pad. I wonder if it is a used technique or is it a bad practice?…
Angs
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16
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2 answers
Why would the VCC/GND pins of an ATtiny26 not be aligned?
In the following pinout diagram for an ATtiny26 microcontroller, a 20-pin IC:
The VCC/AVCC and GND pins aren't aligned. Surely it would be easier for PCB design to connect these by going straight across rather than having to cross (requiring vias,…
JYelton
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16
votes
4 answers
How can I improve this Ethernet differential pair?
This is my first 100 Mbit/s Ethernet project (I am doing it to learn more about differential signals).
I did two things that I don't know if are good or bad in this particular case.
One is to route under the signal transformer. It is only slightly…
Javier Loureiro
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15
votes
1 answer
GPS Design Review (RF Input)
I've designed a PCB in Eagle to host a GPS Receiver module and a GPS patch antenna. The RF input to the module is specified as a 50Ω unbalanced (coaxial) RF input. I used this calculator to calculate the required width and spacing for a co-planar…
vicatcu
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14
votes
7 answers
Autoroute or not?
I made a fairly complex circuit (at least for my level).
After spending a few hours trying to manually autoroute, I had like only 5% finished, and every time run into obstacles of not being able to continue routing.
So I tried to use CircuitMaker's…
Michel Keijzers
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13
votes
2 answers
Creating a high-current bus on a PCB
I'm planning a custom power-distribution / fuse-board for in-car application, but that requires carrying high currents (50A+ @12v*) on a PCB trace. Since I'd like to keep the board cost, and physical size down, can anyone suggest efficient (as in…
John U
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