About the manufacturing of PCBs (Printed Circuit Boards).

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Is there any way to inspect small holes (in micron scale) inside a PCB non-destructively?

I have PCBs with two layers of copper at top and bottom. PCBs with low quality have holes between top layer copper and epoxy. The holes are in near circle shape with 20 - 70 micrometres of diameter ...
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45 views

Professional PCB design

First I want know different solder mask(Paint or sheet) and photoresist(Paint or sheet)? Photoresist(Paint or sheet) use for etching and solder mask use for show pads on PCB. is it so? If I use ...
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42 views

Altium via ring vs. hole clearance rule

I would like to setup different clearance rules for via hole vs the via pad (ring) in Altium. The context is that i am removing unconnected via pads on the inner layers and my board house has ...
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1answer
58 views

Via's without annular ring on internal layers

My PCB layout package (Altium) has an option to define the full stack of a via so one may have different sized annular rings on different layers. I was wondering if it is considered "manufacturable" ...
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2answers
75 views

How an electrical component behave after being exposed to excessive current/voltage? [closed]

I wan't to know more about how to recognize a damaged component due to excessive impulse or constant current exposure. Particularly resistors, ceramic/electrolyte capacitors, protective diodes, ...
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1answer
66 views

Hydrogen Peroxide for PCB Etching

I found 500 mL of hydrogen peroxide. It says 12% and food grade. Normally, before, what I found was 3% only, and there wasn't any note like food grade at all. Is this suitable while etching PCB? Is ...
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3answers
349 views

Panelization (& Depaneling) a Metal Core PCB

What is preferred way to panelise a Metal Core PCB (MCPCB) - V-scoring or Tab-routing? The engineering challenge I am facing is that the boards are meant for production (1,000 qty in the initial ...
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1answer
47 views

How do I make a through-hole via? [duplicate]

Using a simple PCB with copper on both sides but naturally in between, is it feasible for a hobbyist to make through-hole vias like this: It seems there is copper in the via itself, isn't there? ...
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47 views

PCB Cleaning for Manufacturing

We produce PCBs in quantity on an automated line. We then have been washing them en mass in a spray-washer that looks like a dishwasher. It uses a saponifier with water to dissolve all the crud on the ...
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2answers
421 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 ...
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4answers
343 views

Clear material for UV Box

I have constructed an UV light box using the innards of a commercially available finger nail drying unit consisting of 4* 9w tubes. (should be more than enough). I have had very poor results in ...
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1answer
90 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?
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1answer
62 views

What are “slash sheets”, and how do they relate to PCB substrates?

I am trying to specify the stackup for a PCB. Previously I have used whatever the board house considered to be their "standard" stackup. This time I am looking at using FR-408 (pdf) because of its ...
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1answer
48 views

What are the recommended trace width and clearance on homemade PCB's?

I know that there are multiple processes and lots of variables regarding homemade PCB manufacturing. Using the right tools it is possible to achieve professional levels. I'm concerned for students ...
2
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0answers
55 views

Using a CFL ballast to power 9W UV tubes

I would like to build a low-cost home UV exposure box for PCB manufacturing. Recently my attention was brought to these dirt cheap UV bulbs which are used in manicure drying lamps. I have the ballast ...
4
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3answers
142 views

Is it possible to create a double layer PCB by gluing together two single layer PCBs?

I'm really in a hurry with a university project. I need to finish the first prototype of an electronics board by the end of the week. It's a through hole board, no SMD. Having just single sided ...
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0answers
43 views

Fabrication outputs options are not available in my Altium 13.0

I am using altium 13.0 and just finished very first my pcb layout. I want to now generate the gerber files but the fabrication output options are not showing up. I even tried clicking the "get more ...
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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 ...
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3answers
128 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 ...
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3answers
508 views

SMD Crystal solder(?) problem and any recommended test procedure

I use a 32.768 kHz SMD crystal (datasheet) for a MCU. Here is the layout part of the crystal. Here is a view from an actual PCB I mounted the components by hand-soldering, and produced about 30 ...
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3answers
801 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 ...
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3answers
126 views

Printing the self designed PCB

I have designed the PCB on Eagle. Most of the components are SMD pakages. This is for the first time i have designed the PCB. I want to print this PCB in the industry (Chinese industry) but i have no ...
0
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1answer
105 views

PCB - High current PTH

Some power boards are failing a high current (lightning) test where an MOV lead is used to transfer the current to the bottom of the board - see MOV lead and pad attached. The issue seems to be that ...
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0answers
54 views

0.8mm PCB for a PSU circuit

I am working on a PSU that converts 230 VAC to 12Vdc (0.1 A). The board has the necessary clearance and creepage distances. Would it cause any safety issue (IEC60950) if the 0.8 mm (or 1.2 mm) thick ...
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2answers
817 views

Air gap on isolation space

The below photo belongs to a PSU. I wonder what was the reason of placing air gaps on the 8 mm isolation. Is it to improve the isolation or provide a thermal relief (although there is no component ...
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0answers
38 views

Making PCB for PL2303 at home

I'm new here and this is my first question/post. I'm trying to print a PCB for UART-USB bridge IC PL2303HX (package SSOP28). I designed the board in eagle and printed it using a common HP laser ...
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1answer
76 views

Symmetry in routing

I'm moving a design to an 8"x6" panel, and got thinking as I drew the route layer(white). The cutouts on the right two boards will be routed out. The left cutout will stay with the frame. During ...
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1answer
66 views

From what pitch should I consider ENIG finish

My design (4-layer, FR4, 1.6mm) has a couple of ICs with 0.5mm pitch pads and some LEDs with 0.4mm pitch pads, very small LEDs. Should I consider ENIG (more expensive) or will HASL do the job? I read ...
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2answers
136 views

PCB design cost for 0.4mm pitch bga, 0.1mm drill hole, 4-layer routing using via-in-pad [closed]

I am doing a development board for a IC with 36 WLCSP package. My PCB layout has 16 via over pads, minimum 0.1mm drill holes, 4-layers. I need to fabricate my PCB. And I could not find a exact pricing ...
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38 views

Convert Gerber files to scaled PNG's for A4 size paper

I need to export GERBER files to PNG's or PDF's so that I can print it on a A4 size paper and not loose the scaling, obviously to avoid mis fits of chips and components. I have gerbv installed on ...
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0answers
37 views

BOM/OPL parts help before PCB fab

I am completing my first official PCB project. I am outsourcing the PCB fab to Seeeed Studio. I was wondering if any of you might be able to shed some light on my issue. I am using their PCB ...
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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 ...
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1answer
124 views

Understanding PCB layer stack-up shorthand notation [2:(1(2+345*67)*16):7]

I was given a PCB layer stackup specification like this: [2:(1(2+345*67)*16):7] For an 8 layer blind via setup. Could someone provide a reference to decode this ...
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1answer
99 views

Should PCBs be rinsed after being cleaned with IPA?

A lot of people recommend using 99% IPA to clean flux (and other stuff) off PCBs. I haven't been rinsing off boards after cleaning with IPA as to my knowledge it's not corrosive, but I'd like to hear ...
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1answer
217 views

Silk-screened 'buttons' on a touch-tone phone?

I've been taking apart a recent, standard touch tone phone with the aim for automated dialing via a separate MCU with transistors activating the contacts (Smirk. An assistive technologies project ...
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0answers
66 views

fiducials on a panel

have a little question about fiducials: My Layouter/My Boss likes to use 3 fiducials on the panelframe and one fiducial on each individual board in the panel. My job is to build the program for the ...
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0answers
87 views

What to look for in a CNC PCB router?

When shopping for CNC routers for milling PCBs, there are some specific tools and others that seem to be fit but are meant for other types of works (typically engraving wood or advertisement). For ...
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5answers
296 views

Correct way to define board outline?

I'm a student and am almost ready to have a PCB I designed fabricated, but I'm confused about how the board outline should be defined. Here's what I currently have: I also have a 20mil keepout ...
2
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2answers
693 views

Eagle - non solder mask defined (NSMD) pads

I am designing a PCB layout in Eagle and in the datasheet of my modul it is said that "Non solder mask defined (NSMD) type is recommended for the solder pads on the PCB". Does it mean that there will ...
4
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3answers
1k views

PCB opaque coating for anti reverse engineering?

Im trying to find a coating for my PCB in order to protect it from reverse engineering. I want it opaque, non-conductive and with a low thermal resistance. Basically I do not want that someone ...
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1answer
79 views

Should courtyard information be included in gerber files for manufacture?

I just used 4pcb's free DFM checker and it doesn't like the fact that the courtyard line widths on my board are 1.968mils (what Altium generated in the IPC component wizard). It's also complaining ...
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1answer
281 views

What is the black thing on the circuit [duplicate]

What is the black thing on the below circuit? Is it used to hide the IC (or other components) that is used on the circuit? What material is it?
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5answers
214 views

How to order a custom PCB

I need a tiny PCB for a tiny IC. Is this something I have to design in autocad? Do I have to go to a shop to print it for me? Ultimately I want to be able to flux solder the IC on the tiny board so ...
4
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1answer
163 views

LED module design considerations for an aluminium board

I need to design a LED module something similar to below. Could anyone who is experience tell me if there is any SW (or tools) to determine how to place the LEDs to have a good and evenly ...
0
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1answer
69 views

What is the recommended exposure time for presentisized positive photoresist board? [duplicate]

What is the recommended exposure time for presentisized positive photoresist board using UV light, fluorescent light, CFL bulb and (will it also work with LED light)? How do we also determine if the ...
0
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1answer
98 views

How multi layer PCB are connected

I've been watching videos how to make PCB at home and I understand the process. But none of them shows how 2 sides are connected, I see on some PCBs there are some circular end points, so it must be ...
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1answer
118 views

Twisted pair coil embedded on a PCB

Has anyone tried twisting very thin wires(of order 100 microns) and then sandwiching it in between 2 layers of a multilayer PCB? I have a problem of EMI and looks like twisted pair is the only ...
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1answer
100 views

Question about a dimension in this IC package drawing

this is the first time I'm making a PCB layout, so I'm not too familiar with datasheets. The picture below shows a diagram for an IC I'm using. The datasheet says all dimensions are in mm. However, ...
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2answers
103 views

What are the plated holes on this PCB for?

In the top left corner of this snapshot, you can see a bonafide test point, TP12. Slightly down and to the right of TP12 you can see an exposed copper pad, also likely a test point. What I am ...
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2answers
77 views

Inkjet Printers+lamp+unused pcb can It work? [closed]

So suppose I have design x Can I print design x inverted onto paper, shine a lamp on it above unused pcb and make a printed pcb? Sorry for my ignorance Cheers!