BITECH Engineering Notes · ~7 min read · Updated 2026-07-26
In short: Every unit we ship — not a statistical sample — passes an 18-hour full-load burn-in on the bare mainboard, a full interface and function test across CAN, serial, Ethernet, display, storage and I/O, then another 18-hour burn-in in the assembled enclosure. Roughly two working days of testing per unit before it leaves Shenzhen. Serial-number traceable, component-lot logged. If something is going to fail, we want it to fail on our bench — not on your production line.
Anyone can pass QC on a batch of pristine boards. The problem in industrial hardware isn’t the boards that work — it’s the 1 to 2% that would have died in month three, and the fact that you can’t tell which ones just by looking at them.
Statistical sampling doesn’t catch those. A random 5% AQL check that passes says nothing about the 95% that weren’t checked. In consumer electronics that’s an acceptable trade-off. In a fanless PC bolted to an AMR chassis or riding on a vehicle bus, one dead unit is a service call, a customer complaint and a chunk of your margin.
So we don’t sample. Every unit gets the same test.
The three stages, in order
Testing runs in three sequential stages — bare-board burn-in, full interface & function test, assembled burn-in — and a unit doesn’t advance until it passes the one before.
| Stage | What runs | Duration | What it catches |
|---|---|---|---|
| 1. Bare-board burn-in | Mainboard powered up, all cores under sustained full load, DDR memory stress, storage read/write cycling, thermal monitoring on CPU / VRM / DDR | 18 hours | Infant mortality on ICs, marginal solder joints, weak power stages, DDR/storage timing issues that only emerge under sustained heat |
| 2. Interface & function test | Every I/O port exercised individually with real tools: CAN frames via USBCAN protocol analyzer, RS-232/485 via SSCOM, Ethernet link and iperf throughput, USB enumeration and R/W, HDMI/DP output, watchdog, RTC, GPIO, isolated I/O barrier verification | ~1–2 hours | Any dead or degraded port; misplaced components; solder shorts on connectors; wrong BIOS/BSP shipped with the unit |
| 3. Assembled-enclosure burn-in | Unit fully assembled (chassis, thermal path, cables, mounting), re-run full-load burn-in with thermal monitoring at the enclosure surface | 18 hours | Thermal path errors — bad thermal pad placement, missing pad on a VRM, chassis contact issues; anything the bare-board test couldn’t see because the heatsink wasn’t there yet |
Roughly two working days of testing per unit before it ships.
