Thursday, October 18th

Bare Printed Circuit Board Electrical Test

Bare Printed Circuit Board Electrical Test

We can perform a visual inspection following the manufacturing process of a printed circuit board to find any potential problems. While that may work fine for a two-layer PCB, for multi-layer PCBs, it is almost impossible to visually inspect the internal layers once the board has been completed.  Therefore, visual tests are done on inner layers prior to lamination to find any problems and correct them.  However, the only way… Read More

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PCB Design Guide Basics

PCB Design Guide Basics

Circuit Board Components A PCB is a Printed Circuit Board and are made from fiberglass reinforced plastic with the copper wiring in trace form. All the circuit board components are held in position by soldering the components into place after drilling holes in the demarcated areas on the board.  The copper tracks which take the place of traditional wires are more effective and more resistant to damage.  They link all the… Read More

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Measuring ESD Stress on a PCB

Measuring ESD Stress on a PCB

ESD Stress Figure 1. Measured Current Through a Protection Device on a PCB (Vertical Scale = 50 mA/div, Horizontal Scale = 20 ns/div) Abstract: (ESD Stress) Measuring voltage stress on components on a PCB under ESD stress conditions can be difficult as the ESD noise can inject error in the measurement. Often this error is larger than the voltage of the stress to be measured. A method of measuring voltage stress… Read More

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The Digispark Arduino Enabled USB Board

The Digispark Arduino Enabled USB Board

Digispark Digispark: I wanted to share with you a cool new product for the hobbyist and test engineers out there. Bay Area Circuits has had the privilege to be building the bare PCBs in this project. Many are familiar with the Arduino test chips used to make all kinds of little electronics projects. Erik Kettenburg over at Digispark thought there would be a better way to make use of these… Read More

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PCB Chassis Ground Connections

PCB Chassis Ground Connections

We hope you enjoy another guest blog post from electrical engineer Dough Smith. PCB Chassis Ground Connections       Figure 1. PCB Chassis Ground Connection Abstract: PCB chassis ground connections are often needed in electronic equipment, but if care is not taken, the PCB and the chassis ground structure can become a hi-Q resonant circuit that may cause problems. Background information is given and techniques to avoid problems in designs are… Read More

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Countersinks and Counterbores for Printed Circuit Boards

Countersinks and Counterbores for Printed Circuit Boards

Countersinks and Counterbores This is a continuation of our PCB-101 series. In this post we will talk about Countersinks and Counterbores. First I will highlight what these are and then what we need to know when manufacturing a printed circuit board that needs to have counterbores and countersinks. Countersinks and counterbores are not anything unique to printed circuit boards, by the way. They are used in a variety of manufacturing… Read More

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Photocopier Teardown from EEVblog

Photocopier Teardown from EEVblog

Well here we have Dave Jones again with one of his Teardown Tuesdays. He does a great job of breakdown a wide variety of electronic devices in his weekly show. This time out I wanted to show you this teardown of a Photocopier. The technology in these machines has really changed over the last ten years. They used to be very analog based machines and now they are all digital.… Read More

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Useful Toolkit for Troubleshooting and Characterizing Circuits

Useful Toolkit for Troubleshooting and Characterizing Circuits

PCB Toolkit Enjoy our guest blog post from electrical engineer Doug Smith. Figure 1. Troubleshooting Toolkit including Current Probes, Wire Loops, and Copper Tape PCB Toolkit PCB Toolkit: Abstract: Over the years, I have developed a tool kit of items that are very useful for circuit troubleshooting and verification. Components of the kit are discussed and references given. Discussion: In addition to the normal troubleshooting tools like scope probes, oscilloscopes,… Read More

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Controlled Impedance for Printed Circuit Boards

Controlled Impedance for Printed Circuit Boards

Controlled Impedance: First of all I am not an Electrical Engineer and I do not play one on TV.  This is meant to be a very basic idea of what controlled impedance is and how it relates to printed circuit manufacturing.  I would love to have comments from electrical engineers in the comment section below! What is Controlled Impedance? Electrical impedance is the measure of the opposition (resistance) that a… Read More

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Routing Signals Between PCB Layers – Part 3 Interplane Voltage

Routing Signals Between PCB Layers –  Part 3 Interplane Voltage

Routing Signals Between PCB Layers –  Part 3 Interplane Voltage (Frequency Domain Measurement) (Spectrum Analyzer Screen at 10 dB/div Vertically and 100 MHz/div Horizontally) Abstract: Four layer PCBs are used in a wide variety of applications. However, usually it is necessary for some signal paths to be routed on both the top and bottom signal layers to achieve required routing density. Using a model of a four layer PCB with… Read More

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Rout and Fabrication of Printed Circuit Boards

Rout and Fabrication of Printed Circuit Boards

For the next in our PCB101 series we will be talking about the final fabrication on the board. Once we finished applying the board finishes mentioned in our last post in this series it is time to cut our rout out the individual boards. The boards can be routed out as individual small boards or they may be an array (multiple boards) still connected via tabs or score lines.  This… Read More

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PCB Protection Can be Compromised by Ground Structure

PCB Protection Can be Compromised by Ground Structure

This post is a guest post from Doug Smith.  Doug is an electrical engineer who trains other electrical engineers in EMC Design.  His website emcesd.com is a wealth of information.  We appreciate his contribution to our site. Figure 1. PCB Layout with Noise and Signal Ground Areas Abstract: Printed Circuit Board designers sometimes place protective devices on external signals as they enter a PCB and shunt the current from these devices to… Read More

An Expert’s Guide to PCB Finishes

An Expert’s Guide to PCB Finishes

Applying the surface finish is one of the last steps of manufacturing a printed circuit board. The surface PCB finish is designed to prevent oxidation of the remaining exposed copper, while the soldermask covers the majority of the circuitry. This is important because oxidized copper cannot be soldered. In rare instances, when a printed circuit board requires “body gold,” the finish is applied to the copper prior to the soldermask… Read More

Outer Layer Image and Soldermask

Outer Layer Image and Soldermask

Alright let us do a quick re-cap of what we have covered so far. We have given an overview of some basic materials and the initial process for developing imaging for inner layers. We have covered the lamination and drill process. Now we are coming down the home stretch. Now that the panels are drilled we need to do the outer layer image and copper plating process. That begins with… Read More

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Multi Layer PCB Image Process

Multi Layer PCB Image Process

In our last post we talked about the basic material used to start the PCB manufacturing process. If we were doing a double sided board it would actually be going into drill at this part of the process. We will get to that eventually. What we are going to do is walk through the multilayer process which is a different process initially. We will pick up at drill and the… Read More