About designing the boards which carry the components of an electronic circuit. For questions about getting them built instead use PCB-fabrication. If your question is specific to a certain CAD tool, say which tool and version you are using.

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1answer
50 views

PCB connector to bring out pins on an IC

I have a PCB which has a footprint for an IC. This IC is a TQFP package and has about 144 pins. However, not all the pins are brought out on the PCB. I am ready to desolder the IC from the PCB and put ...
1
vote
1answer
79 views

Help to identify resistor to remove [on hold]

I just bought a solar powered LED light that has a motion sensor and a light sensor. When it is dark, it turns on but very dim. When it detects motion, it turns on full power (not very much...) for 20 ...
0
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0answers
28 views

PCB Documentation for fabrication using allegro

I generally used to design PCB export PDF and create fabrication notes separately. Recently I needed one board to designed by professional and I was surprised to see the complete sheet and fab notes ...
2
votes
1answer
85 views

I2C camera not working 100% of the time

This is my stereoscopic system: I'm using a zedboard to pilot two i2c-camera MT9D111: http://www.dragonwake.com/download/camera/MT9D111/mt9d111_rev5.pdf Camera PCB Information: ...
0
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1answer
28 views

Choosing Stepper Motor - Driver Combination

This is my first attempt at designing/building my own circuit and PCB, so please bear with me. I am building a small, portable device that makes use of a small, accurate motor. My goal is to make the ...
9
votes
4answers
1k views

Hacking Circuits Together Using Existing Schematics

I am working on a prototype using existing breakout boards from open source hardware manufacturers (Sparkfun, Adafruit, Teensy etc...). Everything is going great! I am at the stage where I'd like to ...
7
votes
3answers
186 views

How to Connect USB/Ethernet Shields to Chassis or Digital Grounds

I have a PCB with a few USB and RJ-45 Ethernet connectors on one side. I'm quite confused as to how exactly I'm supposed to be hooking up the SHIELD pins on them though. This is for a host device ...
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votes
2answers
63 views

ADC/DAC module with TCP/IP communication

I have a project: conception and realization of a module that converts Analog to digital signals (A/D converter) and digital to analog signals (D/A converter). To communicate with this module, I will ...
4
votes
1answer
55 views

Distributing Ground and Clock Between ADC and FPGA on Separate PCBs

This question is in reference to my previous question where some suggestions were made that went somewhat off-topic. Basically I have a built a system with an FPGA and very sensitive ADC (sensitive ...
5
votes
1answer
84 views

Separating Two High Speed Digital ICs

Previously, I've designed a PCB incorporating this ADC chip. It has a digital bus of 10 signals some of which are 40MHz. Right now we have a four layer PCB and the ADC is connected directly to a ...
2
votes
1answer
45 views

Extracting footprint existing PCB in Altium

I'm in the process of designing a carrier for an existing PCB. The upper layer of the carrier should contain pads to connect to the holes on the side of the original board. I can re-create the ...
3
votes
4answers
68 views

Is it good to route PCB tracks under a heatsink?

A heat sink is a piece of metal. If the solder mask on a PCB track is broken, it may be dangerous, right? Below is a small heatsink for TO220, seen from bottom.
1
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1answer
30 views

Component keep-out on particular layer in Altium

I'm making a heat sink footprint for TO220 in Altium. I think route tracks under the heat sink is not a good idea. So I want to give the footprint a keep-out, but the keep-out region on Keep-Out layer ...
0
votes
1answer
42 views

designing a pcb breakout board with micro dsubs

I am a beginner in the world of pcbs and I'd like to make a breakout board. The board will be breaking out signals from micro dsubs. There are no other components on the board. What is the simplest ...
-7
votes
1answer
48 views

design pcb cortex M4/7 with tft lcd [closed]

i need to build a pcb for cortex M7 or M4 that connected with tft lcd . so please give me a tips . What is the minimal connection that i need to blink a led? 2/ what are the minimal connection that i ...
1
vote
2answers
110 views

Electric Timer With a Micro-Controller

I am trying to replace some electric timers with some sort of a micro-controller based solution http://www.directindustry.com/industrial-manufacturer/panel-mount-timer-154503.html. I would like to run ...
1
vote
0answers
20 views

SGTL5000 codec noise

I built an audio baseboard for an i.mx6 board built by embeddedarm(ts4900). I used the ubiquitous sgtl5000 codec from freescale. While the end result works ok, I find that the output from the line ...
1
vote
3answers
78 views

What does “No Pin” mean in IC pinout?

Logically i understand that 'No Pin' literally means that there is no physical pin but i would prefer to hear a conformation of this fact by those who has encountered such situation. The thing is ...
1
vote
3answers
69 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 ...
0
votes
2answers
92 views

How to create isolation slots/gaps in eagle CAD

I'm new to PCB, how to create isolation slots or air gaps in PCB using eagle CAD. Thanks
1
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0answers
74 views

PCB isolation strength VS pad-to-pad distance

Is there any estimation regarding the relation between PCB pad to pad distance and isolation strength? If the board is covered with the mask and the minimum distance is 2,9 mm which isolation voltage ...
1
vote
1answer
91 views

Change only one side the roundness in SMD

I'm doing my own component in Eagle for a PCB design. This is the footprint that the manufacturer gives: But I have a problem with the SMD roundness when I try to draw the SMD footprint at the ...
0
votes
1answer
64 views

Guide to effecient/neat circuit design (etch and proto PCB)? [closed]

I'm starting to delve into slightly more complex prototyped PCBs and (eventually) will be etching boards. All the guides I've read have been quite basic about the process, but I would like to know if ...
7
votes
4answers
408 views

Placing a mounting hole partially outside the board

I have a board currently 50x30 mm. And I need to have 4 mounting holes on it. Bad news is that I don't have enough space to place them in regular way. Now I made the following thing: I placed four ...
1
vote
0answers
64 views

Why do PCB traces go back and forth? [duplicate]

Why do traces on PCB's go back and forth? My first thought was it acts as a delay however the length of it should make the delay unnoticeable, if nearly non-existent. Image of example:
2
votes
3answers
257 views

Can I route between the copper pads

I have a PCB layout as shown. My question is can I route the PCB between the copper pads? The purple colour is solder mask. From what I know solder mask is the green stuff on a PCB which covers the ...
3
votes
1answer
43 views

Need help in Altium polygon copper pour selects and deselects using arcs, angles, full circles

This is a follow up question of my previous question. I've done this board using AutoCAD and exported to DXF. After that I used Altium designer to import the DXF file in which the outline turned ...
3
votes
2answers
122 views

Connecting grounds of DC-DC converter at one point

There have been questions regarding connection of grounds of an isolated DC-DC converter. However I could not find anything that discusses whether the two grounds (when connected) should only be ...
6
votes
4answers
314 views

Whats the standard for denoting the orientation of an LED on a PCB?

Whats the standard for denoting the orientation of an LED (or diode in general) when printing a PCB? I'm drawing up a design for students to use in a course and want to make sure I'm not misleading ...
4
votes
1answer
74 views

Altium hide component designators in fabrication ourput gerber

As the title says, is there a way to hide the component designators in the fabrication ourput in Altium AD15? I have a very tight board with 0402 parts very close, so there is no room for the ...
7
votes
1answer
339 views

PCB microcontroller layout in a mixed-signal system

This is a direct continuation of this question. So here's my layout, what do you think about the microcontroller side? EDIT: based on Armandas' answer, I'm now under the impression that the ...
0
votes
1answer
40 views

How to programme constant current of a LED Driver for various current levels?

I need to design a backlight unit that will change its duty cycle and constant LED current via a microcontroller. My supply is a SMPS with 12V - 20A output. I need to drive 16 * 16 = 256 LEDs(seperate ...
8
votes
3answers
321 views

Details on PCB layout for microcontroller

Update: the follow-up question shows my take on the resulting PCB layout. I'm laying out my first board with a uC (I've got a reasonable amount of experience in using and programming embedded ...
7
votes
3answers
343 views

Angles and measurement - PCB design help

I have started doing PCB design from last month and very new to this. I have done tiny bits on eagle cad and Altium cad but still learning things everyday. Now I got a challenging board to do. Though ...
1
vote
2answers
57 views

Board to Wire Connector Type used between Small Display and Main PCB

I'm in the process of designing a PCB/Prototype and looking at different types of board-to-wire type connectors. In particular, I want to connect an SPI OLED display to the main PCB. It needs to be ...
0
votes
1answer
44 views

How do I decide which track mode to use for different ampere ratings

There are different tracks in proteus ARES like T15, T40 etc. What is their unit? How do I decide which track mode to use for different ampere ratings?
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votes
0answers
53 views

orcad 16.6 4-layer pcb design

I'm new to four layer pcb design. I have designed two layer PCBs using orcad 16.6. So I'm somewhat familiar with orcad tools. But I'm going to design a circuit which includes ECG filter, USB lines, ...
0
votes
1answer
85 views

Designing a custom arduino pro board

Inspired by the Arduino Pro and a circular LED clock that I have made last year, I am designing a new small circular board similar to both in some ways. The Arduino Pro is a great board, but it lacks ...
1
vote
1answer
46 views

Eagle PCB design: wire names for multiple power/gnd pins

I am working on a schematic using Eagle (free version, v7.5) for a part that has multiple VCC/VBAT pins with each pin requiring a decoupling capacitor. Currently, my schematic looks like the one ...
0
votes
1answer
61 views

Please review my board design

This is a follow up to my question from yesterday about my schematic Please review my RGB Controller I've fixed the incorrect DC jack component that was present in my previous question, along with ...
4
votes
1answer
48 views

Problem with USB mini-B surface mount right angle connector

This question is about the advisability of continuing to use a USB mini-B right angle surface mount connector in my pcb designs. On occasion we see one of these connectors peel back or delaminate off ...
12
votes
2answers
374 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
158 views

How do I lay out PCB traces for a given “differential impedance”

This is an attempt to craft a good general question and answer for a topic that's been asked before, but only in specific situations. Could you describe what I need to know, prior to laying out a ...
0
votes
1answer
32 views

Can someone help to find / create / add a device in Eagle Library?

I want to use FSL176MRT a integrated Pulse Width Modulation (PWM) controller and SenseFET IC in my SMPS's PCB design in EAGLE. It is not available in any library. Its a 6 lead TO-220 package device ...
9
votes
1answer
506 views

What does this schematic symbol mean (similar to solder bridge)?

this symbol is similar to solder bridge, but there is a connection on both end. what does this symbol mean, and what is the equivalent pcb for this symbol
-1
votes
1answer
57 views

PCB house raising through hole pad error

A fab house is raising a strange error on through hole pad connections. In the top layer all connections are made but they are saying the bottom layer is left unconnected. Its a breakout board for a ...
0
votes
4answers
74 views

Is it a good habit to route wire under chip resistor/capacitor?

Is it good/safe to route under resistor/capacitor? As below, it's a 0.5mm wire under a 1206 chip resistor.
0
votes
2answers
55 views

where i can find allwinner library for eagle

I work in a project using Allwinner a10 CPU and eagle software i did't find the library I already tried to searched in google and github many time for Allwinner a10 library for eagle software but I ...
2
votes
1answer
54 views

How can I mirror a group of components and wires across a line in eagle, without having it switch board sides?

I want to design a board that is symmetrical - I have designed the left side, and now I want to copy the components and wires to the right side such that it is "mirrored" across the center line - what ...
3
votes
1answer
70 views

Eagle CAD license board limitation: area or edges?

I am deciding on which license to get for the currnt Eagle Cad 7.x (December 2015). There are a few options to consider regarding the PCB size limitations: Standard: 160mmx100mm routing area Pro: ...