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.

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0
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2answers
58 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
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1answer
45 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
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1answer
43 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 ...
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3answers
71 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
57 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
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2answers
378 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
40 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
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1answer
88 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
89 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
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2answers
84 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
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1answer
128 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
301 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
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1answer
58 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
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1answer
53 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
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1answer
1k 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
224 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
162 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
66 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
164 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
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1answer
66 views

Eagle cad dimension measurement showing on tob 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
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1answer
184 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
179 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
1k 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
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1answer
75 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
485 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
55 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
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1answer
197 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
132 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
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2answers
2k 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
154 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
621 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
4k 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
648 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
87 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
818 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
876 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
265 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 ...
1
vote
1answer
224 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
241 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
874 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
81 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
420 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 ...
2
votes
1answer
88 views

Eagle: Pins on FPGA exchangeable, depending on configuration

I'm trying to do the PCB design, using Eagle, for a small board with an FPGA that basically just routes the I/O lines to the outside. So, for the purpose of routing this board, the pins are basically ...
2
votes
1answer
2k views

Where is Cadence's Allegro Design Entry HDL 16.5 Snap o Grid Option?

I am looking for the snap to grid option? Any idea how to enable it? I did try looking on Cadence forums and documentations, but I did not find anything. Also any idea how I can move ...
10
votes
2answers
1k views

Acute angle routes in PCB

Following is from a PCB that I am presently working on. That particular path signals are of 100-400kHz signals. Is there any problem in having routes of this kind?
0
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1answer
471 views

Altium trace width rule applied to blanket only

In Altium, I set a rule for PCB trace width and clearances for a high current net but I only want it applied to that blanket that I have created in the schematic. I have monitoring lines that wont be ...
1
vote
2answers
305 views

Have I routed this PCB correctly per the schematic

This is my first PCB for production, and I'm not sure if I've correctly routed it. Mostly I'm concerned about trace running from pin 5 of IC1 to C3/C4 and how that picks up the +5V, which I've routed ...
1
vote
1answer
394 views

Routing rules for components in Altium

Is there a way to make a speciffic routing rule applicable only for selected components (or component class)? I want to define some "routing width" rules that will start routing the same net (e.g. ...
0
votes
1answer
450 views

How do I create “beveled” T-intersection traces in Eagle CAD?

Frequently it is convenient to route traces on a PCB such that some other traces or pads are at right angles to a common bus. However, this creates "T" intersections which have 90° angles, which can ...
2
votes
2answers
4k views

Any-angle routing in Altium?

I have a design with a very thin and curvy board shape, so any-angle routing is absolutely required. My favorite EDA software is Altium, so right now I have only two options, both bad, for how to ...