Progress Update (PCB Reversing)

In The Art of PCB Reverse Engineering I laid out detailed steps and procedures on how to recover the schematics from a physical PCB, from determining the board's accessibility, identifying components and creating a bill of materials (BOM), removing conformal coating if it is present, to gathering parts datasheet and information as a pre-requisite preparation prior to the actual work.

Systematic documentation of the process and strategic approaches for different PCB types are just as important, and I took great pains to show how this is done using Microsoft Visio as the diagramming tool of choice, first to create a layout diagram populated with component symbols that are either simple (basic geometrical entities) or smart (Visio's Smartshapes that are embedded with data and formulas), and on to producing schematics that are consistent and readable using the netlist extracted from the physical board. There are also numerous advanced topics included in that book as well.

This sequel to my first book, though aimed at giving readers a broad sweep of the industrial tools and techniques on PCB-RE,  will nevertheless still be incomplete without some mention on manual PCB-RE. My intention is to familiarize readers with the steps involved without overbearing with details, and at the same time to look at PCB-RE from a design perspective to understand important characteristics of different PCB types and in the process, gain a better chance of success.

A reader put forth this feedback to me:

Perhaps what I would like to see more in the midst of explaining component features and how to draw them in Visio is also the different characteristics and features a PCB can hold. It'll be helpful to explain why traces are drawn in a certain way, which may tell you a lot about the PCB as well as its layer design and characteristics such as grounding, shielding, vias and all the rules it must adhere to etc.

Though PCB design is not my forte, I have experimented with different PCB layout programs and know the importance of design and electrical rules checks, and had worked on quite a variety of PCBs to appreciate their underlying design considerations. Generally, the three main concerns are:

1. Electromagnetic interference (EMI)

2. Signal integrity (SI)

3. Thermal management

These factors, plus some others, ultimately affect how components are placed, the way copper layers and power planes are arranged, how signals are routed, the kind of vias to use, and whether additional heat dissipation measures are required, etc. 

And as requested by the above reader, I will first list the generic steps involved in reversing each type of PCB——digital, analog, mixed-signal, power——and then follow on with some design specifics related to each PCB type. The sequel book content will therefore compliment The Art of PCB Reverse Engineering in this respect.