Questions relating to the routing of printed circuit boards (PCBs) which involves the placement of tracks on the board. It may be performed manually however many PCB CAD programs provide an autorouter to assist in the process.

learn more… | top users | synonyms

3
votes
2answers
39 views

Interactive Diff Pair Length Tuning Altium Designer

I am using Altium Designer and sometimes (very often) when I am using the Interactive Diff Pair Length Tuning even when I click properly on the wire I have this error : As said in the response below ...
9
votes
4answers
681 views

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 ...
1
vote
1answer
50 views

2 Layer power routing with mixed signals

I am working on a BLE Gamepad project using a module based on the Nordic NRF51822. This is the first project I have done that is more complicated then an arduino project so I am likely to make some ...
3
votes
1answer
101 views

Is using vias for split data buses a bad idea?

I've tried searching for this but can't seem to find the answer I'm looking for. I'm designing my first PCB and I'm having trouble routing data lines without making the board large. For example, I ...
1
vote
1answer
67 views

Does a Ground plane in Eagle still need connections?

Before I added a ground plane my ratsnest was showing the needed GND connections which I still needed to make. I added a Ground plane and now they are automatically gone. Is this normal? I can ...
0
votes
0answers
31 views

Remove GND lines from EAGLE's ratsnest [duplicate]

I was wondering whether or not its possible to remove the GND net lines from the ratsnest in EAGLE. It is showing me a whole bunch of routing that has to be done for the GND but since I'm working ...
1
vote
2answers
29 views

Transistor level netlist benchmarks

I'm PhD student in CAD/EDA field. My research topic covers VLSI standard cell's layout design and detailed routing. To make my research results more reliable, I would like to test proposed algorithm ...
0
votes
0answers
67 views

Altium interactive routing is always ignoring obstacles

I can cycle through all the modes of interactive routing, but Altium doesn't seem to care. Any trace I lay will just step right over other nets that already exist, with no effort to push or avoid. A ...
0
votes
2answers
66 views

Separating ground planes with different potentials?

Im currently building a signal generator and have a problem with placing multiple different ground planes which have different voltages. The system is powered off of USB, so all my digital logic ...
3
votes
1answer
46 views

Solder balls and routing out of pad corners

I was approached the other day by a co-worker who claims he avoided routing out of corners of smd pads due to higher odds of solder balls forming. I have so far been under the impression that it is ...
0
votes
1answer
53 views

What is a flow table? Openflow

As question asks. What is a flow table? How is it different from forwarding table? This link says: Switching = forwarding by destination MAC Routing = forwarding by destination IP Forwarding ...
1
vote
3answers
76 views

routing of signals

My doubt relates to a routing style of signals. Speed is not the criteria as the signals are not high speed. Kindly refer the image below please - . There are 2 ways to route signals. They are both ...
1
vote
1answer
70 views

Chip antenna, what to do with power and bottom planes

I'm designing a board which uses a chip antenna. According to the datasheet, there should be no copper on all layers under the antenna. There's also should be some ground plane on the top layer with a ...
12
votes
2answers
548 views

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 ...
1
vote
1answer
49 views

FPGA pin assignment for BGA fanout

I'm working on a project that involves multiple (many) BGA packages, namely interface converters such as Ethernet PHYs connected to a central FPGA. I've already worked out a (tentative) layer ...
2
votes
1answer
159 views

Altium Differential Pair Routing Via to Via Clearance

In Altium 14.3 how can one define via to via clearance in differential pair routing to produce a different spacing between via to via and track to track? I defined a design Rule: ...
2
votes
1answer
116 views

Can eagle autoroute same signal on two layers?

I am trying to construct a PCB in Eagle v7.4.0 Light where some tracks are 220 V tracks. They are in a net class of its own. Question is, can I tell eagle to mark these tracks/ratsnest lines to be ...
1
vote
2answers
157 views

Termination resistors with DDR3, are they needed?

I'm using a DSP processor with one chip Micron DDR3 MT41J128M16JT in a project. I read a lot about the termination resistors, but I'm still confused about if I really need those, I didn't start the ...
3
votes
1answer
217 views

Altium Designer - How to make chamfer on 90 degrees tracks?

My need, is what you can read in the title: how can I make chamfer in 90° tracks connections? I've found a way to do that but works only with auto-routing. I want to do it manually. I have Altium ...
7
votes
3answers
318 views

How to connect these pads

I have trouble connecting a THT HDMI Connector to a pcb: The HDMI Connector I'm talking about is this. The holes are too close to go in between them: (The blue line is 0.15mm thick) Is this ...
0
votes
1answer
62 views

What is Partial Crossbar Interconnection

I have difficulties understanding the concept of Partial Crossbar Interconnection and I could not find any reference on internet to read on. I have the photo below from a lecture slide of many years ...
4
votes
1answer
63 views

Routing LFPAK MOSFETs

I am routing a PCB with MOSFETs in LFPAK (aka SOT-669, Power SO8) packages for the 1st time. They look like D2PAK. The manufacturer, NXP, advises to draw identical polygons on top and bottom sides, ...
0
votes
1answer
2k views

Altium: PCB ground plane and routing

OK so I've been asking around and reading how to connect ground pins to ground. Some said create vias to the ground planes. But should I do that for every pin? Because sometimes when I create via to ...
1
vote
1answer
388 views

Altium: PCB routing

I have several questions: I'm not sure how to deal with grounds or Vcc when routing. So I have capacitors/resistors connected to the Vcc of the FPGA, so I connect it directly to the pin. But how do ...
0
votes
2answers
304 views

Altium: Connecting routes through different layers

I know how to route and create vias to connect the track from one layer to the next (i.e. layer A to B then to C). But is it possible to connect tracks from one layer to a specified layer directly ...
1
vote
0answers
87 views

Altium: Routing in different layers brings me back to top layer

Routing on the top layer is fine. But whenever I try to route on a different layer, it automatically brings me back to the top layer and routes there. Am I missing a step? Let me make this more ...
1
vote
1answer
338 views

Altium: the shortcut key +/- don't move me to the next layers

I have created multiple layers from the stack layer manager. Also created vias from layer 1 to 2, and 1 to 3. When I clicked okay, the layer image didn't get updated, meaning it didnt add the vias I ...
0
votes
1answer
98 views

Eagle cad dimension measurement showing on top and bottom layer when creating Gerber files

I have an Eagle design as shown in the 1st image attached. The dimension measurements are on "dimensions" layer 20. When I create Gerber files then look at it in a viewer, I get the measurement ...
0
votes
1answer
248 views

stm32f4 HSE crystal

I'm trying to set up an HSE for my STM32f4, using this crystal. but there are 2 pins : OSC_IN and OSC_OUT, but my crystal only has one output. So what do I link OSC_IN and OUT to ?
3
votes
4answers
201 views

Routing USB2 signals

On this board USB2 signals are routed using smooth lines instead of the usual 45° routing seen on the rest of the board. Does this offer advantages or is this even necessary? A theoretical advantage ...
9
votes
5answers
2k views

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 ...
0
votes
1answer
92 views

Power Supply Router implementation

I am looking for the general approach (technique/strategy, componentry used, etc.) to implement what I am calling a power supply router, although perhaps there is a more precise/accurate term for it. ...
2
votes
3answers
925 views

'Unrouting' a ground plane on Eagle

I have been using Eagle for quite a while now but there is one thing that continues to bother me while I am using it. I have made the ground plane cover the shape of the board, however, when I am ...
3
votes
1answer
58 views

Purpose of deleting internal PAD

I just learned today that, when you're routing the board you can delete the pad of through hole connectors on the internal layout. Some company even ask to delete all the internal pad that are not ...
5
votes
1answer
217 views

Things to be aware of when using voronoi shaped traces

I was thinking of giving voronoi shaped traces (e.g. http://publications.csail.mit.edu/abstracts/abstracts05/rus/rus.html for those who need an example, or just google image search it) a try. In ...
2
votes
1answer
203 views

Should vias be used for every GND connection?

When making a two layer board with the bottom layer being a GND plane, should every GND pad for ICs and passives be directly connected to the GND plane using a via, or should I route all of the GND ...
6
votes
2answers
3k views

Length Matching Differential Pairs

I am routing a PCB with an Ethernet connection and I am having a bit of trouble deciding on how best to route the TX and RX differential pairs. I have done the impedance calculations to figure out the ...
3
votes
1answer
174 views

Altium 'Adaptive' Routing

I recently switched from Mentor Graphics Expedition to Altium 14. I really like a lot of Altiums features but efficient routing still eludes me. In mentor my typical workflow was: Place components ...
3
votes
2answers
734 views

Why we need the PCB Panelised for assembly?

I have a PCB finished in invidividual size for customer but they gave me comment that it can't be used by their assembly vendor and ask me make the new batch for them, When we make the board in 2 up ...
5
votes
4answers
5k views

How can I make a decent ground plane in Eagle?

I've made a couple of simple PCBs as a hobbyist, and for the first time now I want to add a ground plane pour but I'm having some issues. As I have currently understood I need to: Create a polygon ...
4
votes
2answers
704 views

Understanding source and return current flow on PCBs

I'm looking for advice and tips related to PCB board layout and signal+ground trace/track routing. I'm designing a 2-layer analog-only PCB that has several I/O signals leading to and from other ...
2
votes
1answer
94 views

Routing Audio Ground - needed or not?

I'm trying to build a guitar pedal switcher (efectively a box that provides multiple effect loops that can be independently bypassed from a single microprocessor) and while building a working ...
3
votes
1answer
1k views

RMII MAC side routing and signal integrity

I have some signal integrity and EMC questions. In my board LPC1768 RMII interface is connected to LAN8720. Because of pin locations some RMII signals must go through bottom layer. This is a four ...
2
votes
1answer
1k views

DDR4 routing / spacing guidelines

Where can I find the source of routing guidelines for DDR4. I'm talking about things like DQ to DQS timing, maximum length difference in ps for address and command and maybe maximum parallel run ...
3
votes
2answers
376 views

Multiple traces for single connection in Eagle

I'm manually routing a power distribution network in Eagle, and am trying to follow the IC vendor's recommendation to attach vias to the power plane both left and right of the bypass capacitor's ...
2
votes
1answer
254 views

Can I connect all ground connectors via the ground fill?

I am working on a very, very simple two-sided PCB design that connects one 8-pin header with 6 audio jacks, each of which has its right channel and ground connected. All grounds are connected via ...
2
votes
1answer
254 views

Four layer PCB power plane

I need to design a system on a four layer PCB. The layer stack-up from what I know would be signal / components ground plane power signal My problem is, I have a system with a power supply of +-5V ...
3
votes
1answer
1k views

How to route to a hidden pin in Altium

I'm using Altium Designer 14.2.3 and I have a connector on which are always two pins connected to each other. In my schematic library I have configured the Pins to be hidden and connected to the ...
0
votes
2answers
86 views

Power analysis after placement and routing of ASIC

How can I procure the files stating the details of power consumption of the chip after PNR in SOC Cadence Encounter?
3
votes
2answers
453 views

Bypass capacitor placement in Eagle

I've just placed a large FPGA in a QFP package with 144 pins in the middle of my board, and would now like to add bypass capacitors on the power supply pins. The power and ground pins are either next ...