Ensuring Form, Fit, Function Microcircuit Emulation Through Reverse Engineering
Why might you need to reverse engineer a microcircuit?
The Emulation of obsolete microcircuits can be hampered by the lack of technical documentation, in many cases the original manufacturer no longer exists, the Technical Data Package (TDP) is incomplete or was not purchased therefore original technical data is lost. The more information available will help to reduce overall development time and increase first pass success probability.
Sometimes, the only way to recreate the missing data is to reverse engineer an original microcircuit.
A known good, working, original part is electrically tested both functionally and every specified electrical parameter using sophisticated ATE (Automatic Test Equipment) and, when required, traditional instrumentation. Any ambiguities may require additional tests as specified by design engineer.
The resulting measurements of this original device are reviewed relative to the specification requirements and used as a baseline for the detailed design of the Emulation circuit.
From time to time reverse engineering through optical imaging is used to clarify any questions the engineers may have about packaging, or the die layout. Figures 1, A-C, show optical images taken of a packaged part, decapped part, and of the die itself. Pictures of the packaged parts allows designers to confirm any markings seen on the package against known vendor markings. Decapped images shows how the die is connected within the package and if for example, any wire bonds are used for additional grounding, or if any special packages were used to reduce ground bounce. Close-up optical images of the die can reveal die and bond pad sizes, poly and metal widths, gate lengths, and power bussing topology. All useful information to have when before implementing design on an existing Emulation technology.
When little, or no, specification data is available it may be possible to extract the missing data through physical reverse engineering. However, for more complex devices this becomes very time consuming and therefore not practical.
The Emulation programs have in-house physical reverse engineering capabilities to recover design data directly from the silicon die itself.
A combination of high-resolution, full-chip optical and electron-beam imaging is used in conjunction with microcircuit delayering techniques to reconstruct the original CAD files and recover the missing design data. To ensure all the circuit connections, and therefore the complete functionality, is captured, sample ICs under investigation are sequentially imaged after the removal of each circuit layer.
Once the complete technical data is recovered a new microcircuit is designed.
The new design is targeted to one of the Emulation program’s inventoried gate arrays that is best suited to duplicate the original circuit function and timing. The new microcircuit is then manufactured in our in-house, Trusted wafer foundry. The assembled parts are then individually tested over the full temperature and performance range. Screening of package integrity, life test reliability, and the full complement of reliability tests are performed in accordance with MIL-PRF-38535. Only once all the testing is complete and the replacement microcircuit is verified to meet all requirements of the specification, it is then ready for delivery.
Any questions? Contact us!