To My Readers



If this is the first time you're visiting my blog, thank you. Whether you're interested or just curious to find out about PCB reverse engineering (PCB-RE), I hope you'll find something useful here.

This blog contains many snippets of the content in my books to provide a more detailed overall sampling for my would-be readers to be better informed before making the purchase. Of course, the book contains more photos and nice illustrations, as evidence from its cover page. Hopefully, this online trailer version will whet your appetite enough to want to get a copy for yourself.

Top Review

I started doing component level repair of electronics with (and without) schematics more than 40 years ago, which activity often involves reverse-engineering of printed circuit boards. Although over the years my technical interests have shifted into particle beam instrumentation, electron microscopy, and focused ion beam technology fields, till this day——and more often than not——PCB repairs have returned multiple multi-million-dollar accelerators, FIB, and SEM instruments back to operation, delivering great satisfaction and some profit.

Many of the methods described by Keng Tiong in great details are similar to the approaches I've developed, but some of the techniques are different, and as effective and useful as efficient and practical. Systematic approach and collection of useful information presented in his books are not only invaluable for a novice approaching PCB-level reverse engineering, but also very interesting reading and hands-on reference for professionals.

Focus on reverse engineering instead of original design provides unique perspective into workings of electronics, and in my opinion books by Keng Tiong (I've got all three of them) are must-read for anybody trying to develop good understanding of electronics——together with writings by Paul Horowitz and Winfield Hill, Phil Hobbs, Jim Williams, Bob Pease, Howard Johnson and Martin Graham, Sam Goldwasser, and other world's top electronics experts.

Valery Ray
Particle Beam Systems Technologist

Tuesday, May 23, 2017

Components Without Markings

As the size of components get smaller, it becomes impossible to label them intelligibly, or even to label them at all. 

Some manufacturers do provide laser markings on their chip capacitors to prevent surface degradation or induced micro-cracks; these codes are based on the EIA RS 198 standards which use 2- or 3-digit alphanumeric codes to represent capacitance values. With these codes, you can then look up their product datasheet reference to determine the values. For example, A5 = 100,000pF or 100nF, where N denotes the vendor NovaCap.



But what do you do with SMD components without markings?

While you're more likely to encounter chip capacitors with no markings than chip resistors, resolving the latter is a much simpler and straightforward affair. A normal digital multimeter can usually measure resistors in-circuit quite accurately without interference from adjacent components, unless there are parallel resistors or low impedance path across the resistor in question.

Unfortunately there's no way you can measure a capacitor in-circuit due to PCB track capacitances as well as induced lead and bond-wire capacitances of components around it. For the most part, you can get some hint from the usage of these SMD capacitors. You can find out more on this and other topics in the book The Art of PCB Reverse Engineering.
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