Meaning
Design verification reviews evaluate the electrical quality of high-speed data paths on a printed circuit board. Through a signal integrity audit, engineering teams analyze trace routing, impedance mismatches, and crosstalk levels on active buses. This review is performed during the layout stage and after physical board testing.
It ensures that digital signals arrive at their destination without corruption or loss of timing margin.
Interface Measurement
High-frequency instruments measure the actual signals on the physical board. Oscilloscopes with high bandwidth capture the rise times, fall times, and eye diagrams of the high-speed traces. This measurement reveals issues like signal reflections or noise that can cause data corruption.
It confirms that the physical traces match the simulated performance.
Margin Allocation
The audit checks the timing and voltage margins against the chip specifications. Each high-speed interface, such as DDR memory or SPI buses, must have enough margin to handle temperature changes and manufacturing variations. This allocation prevents intermittent system crashes under extreme conditions.
It ensures the design is stable against component tolerance differences.
Hardware Modification
Design changes are recommended when the audit reveals signal quality issues. These changes might include adding termination resistors, widening trace spacing, or changing the board’s layer stackup to provide better ground planes. Implementing these fixes during the prototyping phase is much cheaper than changing a production board.
This audit is a central gatekeeper before the design is approved for mass production. It provides the documentation required to sign off on the layout design and proceed to tooling.
