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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1
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2answers
74 views

SMD size 0805 vs 1206

Using SMD to make the PCB smaller is an easy choice but I'm wondering if using mainly 0805 size is really worth it compared to 1206. I don't want to store a mix of both. These are some pro and cons, ...
-1
votes
2answers
32 views

Altium can't output NC drills file?

I'm about to send my gerber files to OSH park however I'm having trouble generating the drill file in Altium 14.3. The output file is some other format than the Excellon / NC Drills file that the fab ...
0
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0answers
21 views

Hybrid design that includes satellite phone on to a laptop PCB [on hold]

My name is Brzenski and I am an student at college in London, doing Network Engineering and Telecommunications. I am in my final term for an HND and have to do a project. I came up with an idea to ...
1
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1answer
71 views

Is it time to move from a 2 layer board to a 4 layer board

Below are two pictures of a portion of a PCB layout I did. The first shows the signal traces and the second shows the ground pour. U1 is an 8 MHz MCU, U3 an I2C sensor, U4 a RTC, and U2 a boosting ...
6
votes
2answers
252 views

How to connect large traces to pads in PCB?

I am designing a PCB, and 10 A-15 A current is flowing in a trace. I think a 300 thou track should be used for 1 oz Cu-thickness. I see that it is impossible to connect two pads ...
1
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1answer
43 views

Validation of power supply decoupling and oscillator connections in a PCB

I've been learning PCB designing lately to design a small controller board.The board has a micro-controller and its supporting components laid out as shown : . After having gone through some nice ...
1
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0answers
58 views

3v3, 12v Smps: “Design ok!” “Pcb ok!” Why not stable? Please Help

Im working on a project and i need 3v3,5v and 12V in this. I though smps circuits would be better than Linear Regulators. So i choose LM2676-adj IC. I designed schemetics for 3V3-3A SMPS and 12V-3A ...
1
vote
3answers
73 views

Via's in switch mode power supply

I'm using a TPS54386 and currently designing a PCB layout. The data sheet says to avoid via's within a certain loop; I was wondering what would happen or if anything would if I went ahead and placed ...
0
votes
1answer
30 views

How to connect pins with ratsnest connection after netlist transfer in Proteus ARES

I have a schematic file in Proteus-ISIS. I transferred into the ARES, after defining board edge and placing components, I placed 1x5 connector (CON5_1X5_U_FCI). But I could not connect pins of the ...
0
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0answers
54 views

Determine best op-amp order for PCB design

In my current design, I use 3 op-amps from a quad package (DIL 14). One is not used. For the design, it doesn't matter which op-amp is used when, since they should be identical. For example, I'm ...
0
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1answer
43 views

coplanar transmission line on both sides of a four layer board

I am designing a four layer board in which i have to run two 50 ohm traces one at the top and other at the bottom side of the board. I have decided to use Coplanar wave guide for both the traces. I am ...
0
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0answers
49 views

Improving PCB layout for regulator circuit

I've made a layout around an Allegro A4490 triple buck regulator, with four optimization goals: minimize loop area/change in area when switching keep the ground attachment of the input and output ...
2
votes
1answer
60 views

How to draw an elliptical PAD in Eagle

I am trying to design a PCB layout for a component which requires elliptical pads. I am trying to do it with two arcs but I didn't get an ellipse. Can anyone suggest how to draw ellipse on eagle? Is ...
12
votes
1answer
396 views

How to select FR-4 board thickness

The PCB manufacturing house that I use says the board thickness between 0.4mm and 1.6mm are the same cost (I have 2 layer design). What is the benefit of having thinner or thicker board thickness for ...
0
votes
2answers
69 views

Why is my circuit not providing the right voltage to my motor?

I have a circuit which is supposed to vibrate a vibrating motor. The circuit is fairly simple and uses a BJT to step up the current to the motor. The motor also has a capacitor and diode in parallel ...
7
votes
3answers
148 views

High Voltage PCB Design

I want to design a 4 layer PCB with the following voltage levels. GND, 5V, 3.3V and 80V. In the circuit there are some MOSFETs which are driven by 3.3V and MOSFET switch 80V (required current is very ...
5
votes
1answer
85 views

Placing Via's on PCB

I'm designing a PCB for USB 3.0, the specifications for Differential impedance comes at 90 ohms with a tolerance of +- 5 ohms. I've used different calculation tools but when I have to hold these ...
6
votes
2answers
169 views

Mounting hole on a PCB

Here is a picture of 3 mounting holes on three different PCBs. The red one is what I prepared on Eagle CAD and used "hole" button on the left side menu , something like this: Do I need to use ...
4
votes
2answers
76 views

PCB Panelization tool/SW and adding test connections

I prepared 4 different PCB layouts on Eagle CAD and generated Gerber files. As I can see Eagle CAD doesn't have any option to panelization. Is there any free tool/program that can allow me to ...
1
vote
1answer
56 views

Is there some PCB tool that exports to ISIS Proteus [closed]

I'm a CS student and I have to build a project in ISIS Proteus as a semester project, but Proteus' demo version does not allow to save the project. The project must be in Proteus because it is the ...
2
votes
2answers
268 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 ...
1
vote
1answer
64 views

Will crosstalk be induced if signal running in parrallel to power trace?

I haven't come across any mentions of signals running in parallel with power traces. Everyt mention thus far has been two signals to each other. If I have a low amplitude signal (sinusoid < ...
3
votes
6answers
354 views

Manually Drill Vias into PCB

As shown in the photo below, the PCB design was sent for fabrication without the drill data. Is it still possible to drill the via holes so we can save the PCBs? This is a 2 layer board, most of the ...
3
votes
2answers
103 views

Traces under 32kHz Crystal

I am working on a battery powered 2 layer RF design using a 32.768kHz Crystal oscillator with an Atmega328p micro controller. The crystal will run a timer in asynchronous mode as an RTC clock. My pcb ...
0
votes
1answer
51 views

Proteus, Ares, Isis - how to combine LYT and DSN?

I have inherited some old files from a Proteus project, .DSN and .LYT files. Is there any way of combining them into a project file so new Gerbers can be generated etc?
1
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1answer
43 views

Creating Custom Component + Pattern - Diptrace

Right now I am creating the schematic and the final pcb layout of my circuit in Diptrace so that I can etch the PCB myself. I am going to use LM2985-3.3 SMT LDO from Texas Instruments in my circuit ...
0
votes
2answers
71 views

How can I tap into and measure this rf frequency?

I'm new to rf design, although I'm learning rapidly. I've designed a PCB which uses an ultra-wideband (UWB) transceiver. The center frequency is selectable between 3.6GHz and 6.5GHz, with 500MHz ...
3
votes
2answers
293 views

Clock generation on my PCB

I have not a big background in electronics. I am designing a PCB including a MCU (EFM32) and some ICs. I have seen in lots of circuits that they generally add an external Crystal Clock on the board ...
0
votes
1answer
47 views

EAGLE detecting error at Copper Trace intersecting Dimension Outline

The ARDUINO_MEGA part from the Sparkfun Eagle Library is used in my board design. However when performing a DRU check, it seems that there is an error where the top ...
1
vote
0answers
69 views

funny shaped footprint pads & PCB123

I am using PCB123 to do a PCB layout and I have a part with some oddly shaped pads specified in the part's recommended footprint. It seems that in the footprint editor, there are only 3 options for ...
0
votes
0answers
53 views

Custom USB 7 port hub PCB dasiy-chain

I had a schematic laid out for a custom USB 2.0 7-port hub I needed to create for a project of mine. It currently uses Ethernet RJ45 sockets to provide power and data to each hub (2 Ethernet ports for ...
0
votes
1answer
34 views

Impediance mismatch and amplifier question

I am converting an aviation headset to take a Bluetooth signal. The headset speakers are \$150\Omega\$, and the Bluetooth adapter I think is \$10\Omega\$. The mic will not be used. Can anybody ...
-1
votes
1answer
46 views

What bluetooth chip / type should be used for a remote control car? [closed]

I am building a small remote control car to be controlled by bluetooth (iOS and Android). I am having a custom circuit board built, and I want to know what bluetooth chip I should get. I would like ...
2
votes
2answers
729 views

PCB design review: Decoupling, bypassing and grounding

I'm trying to make my own wireless sensor using ATmega microcontroller. I've some basic understanding of electronics but I'm a total amateur when it comes to designing circuits and PCBs. This is just ...
0
votes
2answers
56 views

Testing a board without placing a component

Is there a way to build a (functional) board without placing 1 component? I am designing a PCB and want to have the option to make it work w/ or w/o placing a specific component (X). This component X ...
1
vote
0answers
81 views

Is it OK to place ground plane under transformer?

I have a large transformer (50kHz, ferrite E-core) on the PCB. I want to pass power rails under it on the bottom layer. Should I place a large ground plane on the top layer to shield these power rails ...
0
votes
1answer
63 views

Connecting Terminal Blocks to Second PCB Board

I have a daughterboard with 3.5mm screw terminal blocks (such as Digikey part # 277-5749-ND) that has to be connected to the mainboard, with the daughterboard either parallel or perpendicular to the ...
0
votes
1answer
52 views

KiCAD pin assigment

What would be the best way to connect multiple pins of a module/footprint to a single pin in the schematic in KiCAD? Do I have to edit the module and set the same pin name for the pins I want to ...
0
votes
2answers
86 views

Calculating the Resistor's Power Rating

I'm designing a couple of step-down voltage regulators based on a LM22677 chip (datasheet) and following the example: I want to get 5V and 10V from a 12V supply, but I have concerns regarding the ...
1
vote
1answer
52 views

Orphan polygon not filling

I'm trying to have an area of my PCB with the same geometry on the top and bottom copper layers, but I'm having trouble with the polygon on the top layer. I placed vias on the bottom contacts (which ...
2
votes
0answers
53 views

Is 3dBi PCB etched GSM/GPRS Antenna Possible?

Is it possible to design a GSM/GPRS antenna that has a gain of 3dBi? if not, what is the maximum gain possible with a PCB GSM/GPRS etched antenna? I'm thinking of a PCB sized 11cm long and 5cm width. ...
1
vote
1answer
65 views

Why should PCB design be mirrored before toner transfer?

I am currently designing a PCB to make with the toner transfer method for the first time. I was reading a guide that said to mirror the image before printing it to the paper. However it seems that the ...
0
votes
0answers
62 views

Reverse Engineering Camtastic file to PCB in Altium

I've followed the directions found here but after the step where I extract the netlists, when I export to PCB it gives the following error. ...
1
vote
1answer
65 views

Schottky power diode replacement

I'm trying to implement a 12V to 5V step down voltage regulator with a Texas Instruments LM22677, as suggested in the device datasheet (Pag 12, Fig 20). Regarding the selection of the power diode, TI ...
4
votes
1answer
75 views

ADuM1301 digital isolator - PCB layout question

We are using the ADuM1301 digital isolator in one of our designs. The PCB layout section from the data sheet states: In applications involving high common-mode transients, care should be ...
3
votes
1answer
197 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
88 views

Optimal Capacitor Placement on DC/DC Convertor

I'm trying to decide on the best layout for caps on a DC/DC converter. Which of the following options (or another, unlisted option) is the best choice? GND Out plane with 5V Out going the opposite ...
0
votes
1answer
43 views

Headers and Cable for a LCD and UI?

My current layout consists of two 16 pin (8x2) 2.54mm pitch (shrouded) headers. One is for an 16x2 LCD screen and the other will be for a button interface as well as status LEDs which will be mounted ...
1
vote
2answers
140 views

PCB's with Connectors

Are there any guidelines, standards or rules of thumb to follow when designing a PCB with connectors (USB, ethernet, etc.) that will need to fit into a case with a back panel? More specifically, how ...
7
votes
2answers
284 views

PCB's and designing power connections

I've designed a few PCB's now, but never put much thought into good practices. They were small boards and most of the emphasis was put into just making sure everything that needed to be connected was ...