PCB Reverse Engineering: Reasons for Going Backwards from PCB to Schematic

 
As a general rule of the thumb, people can learn a lot about anything by dissembling the parts. This is the underlying principle of reverse engineering. Reverse engineering is not just used in hardware engineering but is also used in human DNA mapping and computer software development as well. In printed electronics, reverse engineering means to move in the reverse order from PCB to schematics in order to comprehend and examine the existing systems.

Often engineers get confused between PCB clone and PCB reverse engineering designs. PCB clones are when the exact designs are copied. If PCB reverse engineering is not same as manufacturing a clone; then what is it? Actually, going from PCB to schematic allows the circuit designer to recreate a PCB prototype that behaves in an identical way as the original PCB without being a replica. Here are some of the reasons why it is essential to move from PCB to schematic;

1. Replace Obsolete Components with Low Cost Modern Components

One reason to reverse engineer PCB layouts is to identify obsolete components. These components may have been used at the time of manufacturing because of their availability in the market. However, we are well aware of how the semiconductor technology is evolving at such a fast pace that the original components used may have become obsolete or face an environmental compliance issue. PCB to schematic reverse engineering will allow designers to improve the functionality of the electronic circuitry by making use of state of the art components that are cost effective and readily available.

2. Analyzing and Comprehending the Original PCB

PCB reverse engineering is done for teaching and educational purposes in order to understand technology better so that improvements can be suggested publicly. PCB to schematic and netlists are done to tear down the components to analyze how the circuit, process and entire systems work in an integrated environment. At the circuit level, interconnections at transistor and component levels are studied together. At the process level, the patented semiconductor’s packaging and layout characteristics are studied to comprehend how the integrated ICs are built and what are they manufactured from. System analysis fulfils the purpose of understanding how the chips are used in any system.

3. Correct the Corrupted Files or Switch to a New Platform

There may be some corrupted files in the current PCB design which is in desperate need of modification. There is a serious need to migrate to an entirely new platform but you do not possess the bill of materials, PCB design files, netlists and schematics which is necessary for system upgrades. This is where PCB to schematic reverse engineering comes in handy.

4. Copying the Design

Yes, PCB reverse engineering is done to copy the designs; however, it is increasingly difficult to copy exact designs because of the complex VLSI designs in multilayer PCBs. Automated X-rays and photocopying can be used but then again, there will be anomalies in the recreated circuit which would negatively impact the function of the PCB. It is important to note that here in the USA, copyright law allows companies to reproduce the functionality and not its design. If you do intend to replicate the design, then disclosure of the new PCB to schematic details is mandatory. Modification in trace routing and usage of upgraded PCB electronic components also need to be identified.