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.
8
votes
1answer
138 views
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 ...
4
votes
2answers
63 views
Soldering lifted central pin of TO-252-5 package
I found a very nice voltage regulator of ST (LD39300). But the LD39300PT-R has a package with a lifted central pin (TO-252-5, DPak (4 Leads + Tab), TO-252AD).
Here is a photo:
I just want to do a ...
4
votes
1answer
128 views
Its ok use different layers for power?
For example in a double side board I'm using one layer as gnd and the other layer as power, and then I route the whole circuit inside the planes.
Is that ok? Because I saw that usually both sides are ...
-2
votes
1answer
60 views
Altium help with Routing
I am working with a new computer at my company learning Altium. I have created the schematic and the PCB files inside my project and successfully imported everything from the schematic to the PCB. My ...
-1
votes
4answers
104 views
Triangulate with Ping [closed]
Is it hypothetically possible to triangulate the location within any accuracy of a server at an unknown location by using ping times?
9 computers with location known log on to a multiplayer server. ...
0
votes
1answer
101 views
STANAG 3350B pcb guidelines
What are the pcb routing standards that I have to follow for routing STANAG video signals on my pcb? Specifically, what are the impedance requirements? Is it better to route as a stripline or ...
3
votes
1answer
149 views
SPI routing question…Maximum length SPI can be routed
Basically my question is regarding maximum length of SPI routing, and route efficiently in my scenario and any timing issues(Setup and Hold).
I am just explaining my scenario. Please bear with me, it ...
3
votes
1answer
128 views
Power Plane and Decoupling Capacitors Routing
Forgive me for my simplicity. I'm just a hobbyist and not an engineer by trade.
I am trying to make my first 4 layer PCB in Eagle and I have a question I cannot find the answer to regarding power ...
10
votes
1answer
245 views
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 ...
4
votes
2answers
192 views
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 ...
4
votes
2answers
142 views
PCB Design Considerations - Copper Pouring
So after a very long effort, I think I've finally come towards the end of my PCB board design. It's a two layer board with no ground or VCC plains (Re-routing is not an option) as I can't go though ...
1
vote
2answers
119 views
Routing of an ASIC chip - time taken?
In a typical ASIC design cycle, how much time is taken by an EDA tool to complete the routing?
Assume a fairly complex chip (like the Ivy Bridge). I've heard the entire chip design cycle is typically ...
5
votes
3answers
370 views
How to join 3 traces is a PCB?
Usually I route my PCBs never making a 90º turn as best practices recommends, but sometimes there are points were 3 traces must intercept, if I always do 45º turns, in this intersection will be a 90º ...
2
votes
1answer
326 views
How to connect ground planes together
What is the best way to connect ground planes together ?
I know that ground planes are connected together at multiple locations in order to keep a low impedance GND across the whole board and provide ...
1
vote
3answers
274 views
Routing +12V and -12V for audio opamps?
I have 4 opamps which need +12 V and -12 V supply voltage. I have 2-layer PCB and want to keep it that way; the bottom layer is dedicated for GND of course. To keep noise/EMI as low as possible, +12V ...
2
votes
4answers
930 views
How to specify 100 ohm impedance on a pcb gerber
I've been using Altium for several years when I've needed to designed boards. However it's all been for simple analog designs and never anything too technical. I'm now trying to take a jump into a ...
1
vote
0answers
259 views
0.5mm Pitch BGA Fanout - Reasonable Vias, Drills, Traces and Clearances
I'm pretty new to layout and using Altium.
I need to break out a 0.5mm pitch Spartan 6 BGA, I want to use "reasonable" vias, drills, traces, etc... but I don't really know what that means now a ...
5
votes
3answers
284 views
Does there exist an IC that allows on-the-fly routing of signals?
Do there exist ICs with N input pins and N output pins which, either via EEPROM setting or via on-the-fly control by a microcontroller, allow one to route each of the N inputs to ANY of the N outputs?
...
0
votes
1answer
47 views
Routing Current to Many Individual Channels [duplicate]
Possible Duplicate:
How to implement an isolated connection matrix
I need to put current on up to 30 lines; one at a time. What kind of electronics solutions are there to this kind of ...
4
votes
2answers
168 views
Satisfactory Margin for Traces from PCB Edge
I've had problems routing too close to the edge of a PCB before and was wondering if there's a suitable rule-of-thumb that I should use (maybe to put in a design rule in Altium somehow with my ...
2
votes
0answers
521 views
Add external antenna to router with only internal antennas? [closed]
Does anyone know if its possible to add an external antenna to a router with only internal antennas? I'm trying to improve the signal of my Linksys e4200v2. I'd like to add a high gain antenna if ...
20
votes
2answers
495 views
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 ...
9
votes
6answers
2k views
Finding air wires in Eagle
I am almost done routing a board. However, 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 to make Eagle tell me where it is?
1
vote
2answers
873 views
EAGLE PCB How to set drill clearance?
I have designed an land pattern for a micro USB connector. The connector have 2 x 0.9mm drill holes under it.
The problem is the clearance distance around these holes being to big and overlaps the ...
1
vote
0answers
82 views
Simple embeded linux system optimal for wireless routers [closed]
I was considering starting a little project that involves extending the base role of a router to being somewhat of a home server(they're basically linux servers anyway)– but I'm more of a software ...
0
votes
1answer
380 views
Altium Camtastic Auto-Rout PCB Border is routing over edge of board
I typically draw rout tool paths by hand, but I though I would give Altium's built-in router a try. The command I am talking about is Rout->Auto-Rout PCB Border within the CAM document mode.
The ...
9
votes
2answers
315 views
Does pin order matter at all for this RAM?
I am trying to route a pic32 chip to a 128kB SRAM chip and having a bit of a hard time getting all 17 address lines and all 8 data lines connected. I am trying to tie the first 16 address pins to ...
6
votes
2answers
681 views
Sharing an oscillator between two ICs
I have a microcontroller and an FPGA on the same board. If they're both going to run at the same clock speed, can I just use one oscillator to clock them both? There seems like there is something I ...
2
votes
3answers
987 views
SDRAM issue - LPC1788
I have been using an NXP LPC1788 dev board which I have developed my application on (.NET Microframework Cortex-M3 Port).
Everything was well and good on this board, I had no issues with RAM or ...
7
votes
1answer
698 views
My 12 MHz crystal does not oscillate
I am having trouble with a board I have had fabricated. The processor is an NXP LPC1788 Cortex-M3.
I am using a 12 MHz external crystal to clock the processor as recommended in the datasheet.
...
1
vote
5answers
2k views
PCB (Auto-)Routability
Background
I'm working on a fairly dense mixed PTH/SMD (plated through hole / surface mount) component PCB design. I'm using Eagle CAD for it for the schematic capture / layout and I'm using the ...
8
votes
2answers
689 views
Is it normal to have a rats-nest of VCC/GND traces under an IC?
I'm attempting to route a simple board, the first I've done in 15 years since I routed a 12V linear power supply in the equivalent of mspaint. This board consists mainly of an LPC2387, which is an ...
6
votes
4answers
2k views
Changing all via and routing sizes at once (Altium Designer, PCB Design)
I have a completed PCB design drawn by Altium Designer. I want to increase via sizes. But there are too much of them, and changing all of them one by one will be a very long and bothersome work. Is ...
3
votes
3answers
1k views
I2C routing configuration
I have several slave devices communicating with a microcontroller master on an I2C bus. My PCB is only about 1" x 1" and the devices are only communicating at 400 kHz. What is the best way to ...
1
vote
3answers
786 views
CPU considerations for PCB software (routing) when purchasing a new computer
My company uses Altium Designer for PCB design and the most CPU intensive operation seems to be the autorouting.
My question is, when considering a new computer, would it benefit autorouting ...
18
votes
7answers
4k views
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 ...
4
votes
6answers
2k views
Using TopoR with EagleCad
I just learnt of TopoR routing software. It routes PCB traces without grids, with curves and arcs for reduced trace length and vias.
http://www.toporouter.com/
But its not a complete PCB routing ...
16
votes
8answers
6k views
Solid ground-plane vs Hatched ground-plane
So recently when i was routing a PCB , I came across the option to either fill/pour my ground plane with either solid or hatched copper. I've also noticed that the old arduino duemilanove also had a ...
3
votes
1answer
549 views
How do I connect a pin that is not included on the main symbol or any of the gates of an Eagle part?
In Eagle, I've dealt with a couple of parts that have pads that don't seem to be accessible from the schematic: HTSSOP packages with a thermal pad that should be connected to a ground pin; a battery ...
12
votes
9answers
2k views
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 ...
