Automated Boundary Scan Test Vectors for Multi Site Register Verification
Automated multi-site boundary scan verifies module registers by routing broadcast stimulus to parallel sockets with isolated per-site response comparators.
Vector Compression
Meaning
Semiconductor manufacturing test procedures generate massive datasets containing the digital inputs and expected outputs required to check the logic gates of a fabricated chip. Through vector compression, the size of these test stimulus files is reduced to fit within the limited memory of automated test equipment. This optimization process minimizes the time required to load the test patterns from the tester memory into the device under test during high-volume production.
Reduction Technique
Test software tools scan the generated test vector patterns to identify redundant states or don’t-care values. By implementing vector compression, the compiler packs these sparse vectors into a highly concentrated stream. This compressed stream is expanded back to its full size by a hardware block before being applied to the internal scan chains.
Hardware Support
Decompressor logic blocks must be built into the chip design to unpack the data in real time. This requirement means that vector compression relies on dedicated on-chip decompression circuitry to restore the test stimulus on the fly.
Test Efficiency
Reducing the volume of test data directly shortens the duration of the testing cycle for each manufactured device. High-performance microprocessors utilize vector compression to execute millions of test cycles in seconds, which helps lower the overall test cost per unit. This reduction in test time prevents manufacturing bottlenecks and ensures that high-volume shipments meet delivery schedules without sacrificing test coverage.
Test engineers monitor failure logs to confirm that the decompression hardware correctly unpacks the vectors and identifies defects without introducing diagnostic errors.