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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0answers
27 views

Relay EMI. Should I be worried?

I am using PCB soldered relay to switch 8-10A 220V appliance. Out of curiosity, I tried to visualize the EMI being radiated from arc sparking. I attached the GND to Neutral pole of proble and kept the ...
-4
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2answers
43 views

I am interested in circuit designing .How should I start with it from scratch? [on hold]

I am a 2nd year btech student in electronics and communication engineering.
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3answers
20 views

Via fences or pickets important parameters for design

What is more important for EMI shielding effectiveness with respect to guard traces and via fences, the width of the copper trace that circles around the area or the distance between the vias to ...
1
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1answer
56 views

Hot Glue/Epoxy-like substance on DC-DC regulator

I have a board (an evaluation module for a USB-to-HDMI chip from Microchip) that has a feature I haven't seen before. On top of the 3 DC-DC regulators, there is a clear substance that appears to ...
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0answers
33 views

IPCC ,IDC, Molex PCB connectors

I was given to work on a schematic in orCAD Capture and there were some connector labels new to me. I would like to know how theses connectors look so that I could make a successful PCB footprint in ...
0
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0answers
23 views

Eagle swap layers

I would like to swap two layers in the my 4 layer PCB. For example currently the ground plane is the Bottom layer, is there a way to take all the signals in layer 2 and move them to the Bottom layer ...
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1answer
55 views

Fire Alarm Circuit using transistor

This circuit is working inversely on PCB as compare to Proteus Software. In software, when the temperature increases the buzzer is on. This is the desired output, but on PCB this circuit is working ...
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0answers
42 views

Can the decoupling capacitor for WS2812 be further away?

I have (many) sticks of 8x WS2812b already soldered and completed. Now I've read that it would have been a very good idea to include a 100nF capacitor for each chip on Vcc. I haven't designed the ...
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1answer
52 views

Two flyback diodes in parallel across a relay coil?

I'm using relays that contain a flyback diode internally, so no need to add an external flyback diode. However, I want to provide a place on my PCB to possibly stuff a flyback diode in case I would ...
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1answer
52 views

Easy PCB trace width calculation

I've tried this question and this and several other possible duplicates of this question, but I still can't wrap my head around this. I'm using OSHPark for PCB production. They support a minimum of ...
0
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1answer
53 views

PCB track width for MHz frequency

I am designing an DC to AC converter operating at 10MHz. Its a low power converter and the input current is under 2A. What PCB trace width should I use and can someone give me a guideline on how to ...
3
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2answers
398 views

Place a component on specific height above the PCB

what I have as a big issue is the following layout with two connectors. The problem is that the connector K201 (in right bottom) is very close to the frame. This frame will the attached to a device so ...
0
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1answer
37 views

how to calculate power budget calculation for new project? Need basic steps to start

Could you please let me know how to calculate power budgeting of new project. What are the things i need to consider while power budgeting. what are the main points keep in mind while doing safe and ...
3
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2answers
105 views

What's the point of this thick trace in my PCB?

I'm looking at a trace that goes from Pad 2 of a component to pin 22 of the QFN. What's the point of the thick trace at the beginning if it ends up being as small the pin where it is run?
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3answers
69 views

Incorrect drill diameter for Molex 5569 Mini-Fit Header library in Cadsoft Eagle?

I have been working on a simple 2-layer PCB primarily intended for routing various power connections (essentially acting as a power distribution junction) to clean up the cabling in my enclosure. I ...
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0answers
76 views

PCB Ground and Power Plane Design Guidelines

I am converting a design from through hole components to SMT components. The schematic is identica, except the maximum allowable current through an onboard a relay will be halved from 20A to 10A. ...
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1answer
51 views

How can I switch two wires using solid state relays?

I want to add a "reverse" function to a brushless motor ESC - in theory, it can be done by simply switching any two of the three output wires - I would like do to it via solid state relays, but I am ...
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0answers
61 views

Building a solar powered USB charger

Can some one please help me ! I'm new to electronics and I have been building my own basic ones, but I have decided to step it up a little and design this. Could you tell me if it would work ? If ...
0
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1answer
67 views

PCB chip/trace antenna located away from board edge?

I'm looking to design a system that will require a 2.4GHz antenna. The only problem is, every single reference design I find has the antenna situated on at least one board edge. Unfortunately due to ...
2
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0answers
67 views

Altium Designer Unknown Pin

I've been bashing my head against a wall for the last day trying to get this to work.. I have a custom schematic and pcb library, when I try to update my pcb document I get the following error: I ...
2
votes
1answer
269 views

2.4GHz antenna feed routed through pcb via?

I'm working on designing a BLE device, and have settled on using a chip antenna. It seems, however, that my BLE SoC is going to have to be on the underside of the board, which might be significantly ...
0
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1answer
45 views

Voltage drop in Analog inputs due to long traces length

I am using ADS1278 chip. Analog inputs to this chip have been routed in differential pair manner. The differential pair inputs trace length is maximum 9 inch within the board from the ribbon connector ...
2
votes
1answer
75 views

Crystal PCB track

This is my current PCB crystal set up. The crystal run at 16 Mhz. Any thoughts/comment? Links: MCU - Datasheet TI PCB guideline Tiva C - Here
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0answers
45 views

Steps from schmatics to PCB layout - EAGLE

My question is: What are correct steps to route connections in a 4 layer PCB? in EAGLE. I've designed PCB schematics and switched to board, I've placed all components in strategic positions on top ...
2
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3answers
75 views

Can I make a double board at smart prototyping pcb service?

They have a 5x5cm minimum board size. My board is approx. 35x20mm so I can easily put two side-by-side and thus double the board count within this limit. What is the best way to do this? I know how to ...
0
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1answer
58 views

Altium Designer - split plane

I want to make a plane for my supply on my PCB and a plane for my MCU to isolate the MCU from the power supply noise. I found this article in Altium designer resource: But it isn't clear how the ...
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0answers
47 views

Can I use General Purpose Printed Circuit Board for any voltage or current rating?

The thickness and width of the copper pad (1 ounce/ 2 ounce) depends on the current that will pass through it. Can the General Purpose PCB withstand high currents (up to 15/20A)? If not, is there ...
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1answer
83 views

What constitutes a Via-in-Pad?

Would any of the via's in the picture be considered a via-in-pad? or is it only if it's dead center of the pad?
12
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4answers
958 views

Why is it so hard to find component footprints?

When designing PCB's, I find myself very often having to make footprints for a significant portion of the components on my board. This tends to be very time-consuming, as (in Altium at least), ...
0
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0answers
42 views

how to create connectors for hollow pad in Fritzing

I have manage to create a circular hollow pad that I want around a PCB. Now I would like to add the connectors so I could attach parts to it and I could not manage to open the file in Fritzing part ...
9
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3answers
960 views

What does a race condition mean?

I'm a new electrical engineer so bear with me. I hear some of the other engineers I work with talk about a race condition that exists in one of our circuits. What does that mean?
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1answer
67 views

Reused MCU unit does not work

I had a board with ATMEGA16 (SMD package) micro controller and I had to program through ICSP and it was working fine. Later I needed to make some changes on the board. So I designed a new board and ...
1
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3answers
74 views

PCB Holes Too Small to Fit Component

Based on the VSK-S25 datasheet which states the holes to have a diameter of 1.5 mm, I used the following values in EAGLE When the PCB is made, it turns out that the pins of VSK-S25 are too ...
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1answer
44 views

Two 2.4GHz radio modules (XBee+Bluetooth) on same PCB. How to minimize interference?

I'm designing a PCB with XBee radio module and a bluetooth module (RFDuino SMD with XBee 2mW Radio). Since both of these modules are using 2.4GHz, are there any special consideration about how to ...
0
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2answers
121 views

VSSOP-8 Package Footprint

I am trying to create a footprint for a LMR61428 but the datasheet (linked) only has the package outline and nothing for the recommended land pattern, or footp for a PCB design. I found this image on ...
14
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3answers
2k views

Why are vias bad?

I am designing a PCB with EAGLE and saw that it was trying to limit the amount of vias through the PCB. Why do you want less vias? Why are they bad? Do they bring extra manufacturing cost or is it ...
0
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2answers
41 views

Function of undocumented pads on PCB mount power module

I'm hoping someone may be able to explain to me why are there extra pads on the bottom of APXW003 DC/DC SMPS PCB mount module from ProLynx series from GE Industrial. I am doing a design and it turns ...
0
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3answers
77 views

Autodesk Autocad for PCB design

I recently completed an Advanced Diploma level course subject for PCB design that taught Autocad as the design software. Whilst I am aware of the power of Autocad my subsequent surveying of ...
0
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3answers
92 views

PCB design few questions

Quick couple of questions, I am designing my first PCB and want to have a few boards prototyped with OSH Park. For a board I will be manually soldering components to, will I need to include a tCream ...
0
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1answer
29 views

Altium Design Rule - Selecting Pads Whose Parent Component is not type “No BOM”

I can create a query to select only pads and a query to select only components who are not type "No BOM", but I can't seem to find a way to put these together to create a design rule that only selects ...
1
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2answers
348 views

Weird capacitor looking things shows up in altium when I zoom into the pcb layout

I am using altium for first time for my little circuit project. My layout start showing these weird capacitor looking things in PCB layout. What exactly are they and what are they used for and how do ...
0
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0answers
45 views

Trace clearance error with Altium auto-route

Here is the picture of my PCB auto-routing result. Routes are placed too close to SMD pads. Less than 0.2 mm, which written in Clearance rule. I use Altium Designer 14.1 so I can't set clearance ...
3
votes
1answer
67 views

Rotated component placement in Altium

Here Altium PCB on the picture. I rotate component on 45 degree and place it on the PCB. What is gray area under the component? Should it be rotated also? Can it be a problem if it s not rotated? ...
0
votes
1answer
60 views

Eagle will not finish auto routing?

Using Eagle for mac, I am trying to autoroute the board. I have set the trace width to 8. He start the process and it takes him about 2 minutes, than he stops at some point and show the next ...
0
votes
0answers
32 views

No trace in the pcb gerber from Eagle?

I use Eagle to create gerber files. Here is the gerber file job : ...
4
votes
2answers
74 views

Design question regarding high current wires running below PCB

I am working on a layout that will look similar (not final) to the illustration below. There are three high gauge wires (red) 3x230VAC passing directly below the PCB (isolation touching the PCB) that ...
0
votes
2answers
85 views

PCB manufactoring-There shouldn't be bottom silkscreen selected?

I use Eagle to create gerber files . When i am trying to check my zip gerber, in 4pcb.com i get this message : ...
7
votes
3answers
441 views

What are the different grounds on a PCB?

I am working with boost converters recently. I have problem which you can find here. After going through the datasheet several times I encountered the special focus on the ground plane. It talks about ...
0
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1answer
46 views

Stop mask error upon running DRC in Eagle 7.3.0

I'm working on my first board layout using Eagle (7.3.0). I've got the layout done, but when I run DRC, I get a number of Stop Mask errors: These seem to be due to small rectangles on the tStop ...
8
votes
3answers
791 views

How to cut costs when fabricating large PCBs?

I've looked online at PCB fabrication companies, and they invariably price their boards according to the size of the board as the primary factor. Why is this? The physical board itself isn't that ...