Normal workload
Run long enough to reach steady-state behavior and, for loop recording, at least one wrap-around cycle.
Device validation workflow
A microSD sample test that can support repeat purchasing.
A card that mounts once has not completed validation. Capture the host, firmware, workload, edge cases and approved supply configuration.
Decision rule
Approve a card configuration, not only a capacity label. The approval record should connect device test results to the order and batch.
1. Freeze the test context.
Device model, controller and firmware version
Capacity, card standard, file system and required speed marks
Workload: file sizes, bitrate, write duty, read/write mix and retention
Power, temperature and installation conditions
Card sample identity and supplier configuration reference
2. Test normal use and edge conditions.
Restart and power interruption
Check remount, recording recovery, incomplete-file handling and warning behavior.
Full-card behavior
Verify overwrite policy, file indexing, deletion and usable-space reporting.
Representative units
Repeat on more than one device and more than one card before a production decision.
3. Keep a useful approval and failure record.
Approved device/firmware/card configuration and test date
Test duration, data written, temperatures and pass/fail criteria
Failure timestamp, device log, card identity and reproducible steps
Decision owner, exceptions and conditions for retest after a change
Method & sources
Use the method inside its stated limits.
Method: YOULEN buyer-support working method. It organizes the information needed to discuss a repeatable device test; it is not an SD Association test protocol or a product certification.
Limitations: The device owner must define pass/fail criteria, duration, environmental limits and sample size for the actual product. Supplier and device records must be connected before repeat purchasing.
Content owner: Shenzhen Youlen Electronics Co., Ltd. overseas B2B project. Reviewed and updated: 5 August 2026.