Reliability Data

mpbbldr 10 hours ago

We are performing a reliability analysis on a product that contains a Nordic Semiconductor nRF52840-QIAA-F.

Can you provide the reliability (FIT) data for this component?

Best regards,

Marty Best

0 TEK0 3 minutes ago

Thread Subject: Reliability Data / FIT Rate / MTBF for Nordic SoCs

If you’re pulling together an FMEA (Failure Mode and Effects Analysis), a RAMS analysis, or a Telcordia SR-332 / MIL-HDBK-217 reliability prediction for compliance or production sign-off, here is the breakdown of what Nordic provides, what the baseline numbers look like, and how to treat them in a real-world design.

1. How to Get the Official Qualification Report (The Paperwork)

Nordic Semiconductor does not publish full reliability and qualification reports openly in public datasheets because package-level stress data and foundry wafer lot qualification are proprietary and frequently tied to specific silicon revisions and package codes.

Open a Private Support Case: Go to the Nordic DevZone portal, create a ticket, and set the case to Private.
What to specify in your request:
- Exact part number and package code (e.g., nRF52840-QIAA-F vs nRF52840-CKAA WLCSP, nRF5340-QKAA, etc.).
- Build code/hardware revision (found on the chip package top marking).
- Target reliability standard (e.g., JEDEC JESD47, Telcordia SR-332, ISO 26262, IEC 60601 / ISO 13485).
Alternative Route: If you have an assigned Nordic Regional Sales Manager (RSM) or a Field Application Engineer (FAE) through your distributor (Avnet, Arrow, Mouser, etc.), request the Product Reliability and Qualification Report (QR) under your company's NDA.

2. Standard Baseline Metrics (The "Cheat Sheet")

For rapid initial system calculations, Nordic’s qualification data complies with standard JEDEC (JESD47 / JESD22) qualification methodologies:

Parameter	Standard Value / Typical Nordic Baseline	Notes
FIT (Failures In Time)	$FIT\sim 50\text{ to }51\text{ FIT}$ ( $60%60\%$ Confidence Level, $Ta=55∘CT_a = 55^\circ\text{C}$ )	Failures per $10^9$ device-operating hours. Derived from High-Temperature Operating Life (HTOL, JESD22-A108).
MTBF / MTTF	$hours\approx 1.96 \times 10^7\text{ hours}$ ( $years\approx 2,200\text{ years}$ )	Calculated simply as $109FIT\frac{10^9}{\text{FIT}}$ at $55∘C55^\circ\text{C}$ .
Activation Energy ( $E_a$ )	$eV0.7\text{ eV}$	Used for Arrhenius equation temperature acceleration factors to derate at higher ambient/junction temps ( $85∘C85^\circ\text{C}$ or $105∘C105^\circ\text{C}$ ).
Flash Endurance	$cycles10,000\text{ write/erase cycles}$	NVMC endurance per page (varies slightly by family; check specific Product Spec).
Data Retention	$85∘C10\text{ years at }85^\circ\text{C}$	Heavily dependent on operating temperature.
ESD Immunity	$kV\pm 2\text{ to }\pm 4\text{ kV}$ HBM / $V\pm 500\text{ to }\pm 1000\text{ V}$ CDM	JESD22-A114 (Human Body) / JESD22-C101 (Charged Device).
Moisture Sensitivity	MSL 2 or MSL 3 (depending on package)	Refer to packaging specifications for J-STD-020 floor life and bake-out requirements.

3. Temperature Derating (Arrhenius Scaling)

If your product runs in an industrial or high-heat environment (e.g., $Tambient=85∘CT_{\text{ambient}} = 85^\circ\text{C}$ ), do not use the raw $55∘C55^\circ\text{C}$ FIT number. Apply the Arrhenius acceleration factor:

$\exp\left( \frac{E_a}{k_B} \left( \frac{1}{T_{\text{use}}} - \frac{1}{T_{\text{stress}}} \right) \right)$

$eVE_a = 0.7\text{ eV}$
$eV/Kk_B = 8.617 \times 10^{-5}\text{ eV/K}$
Note that junction temperature ( $Tj=Ta+Pdissipated×θJAT_j = T_a + P_{\text{dissipated}} \times \theta_{JA}$ ) must remain within absolute maximum ratings (typically $85∘C85^\circ\text{C}$ for standard grade, $105∘C105^\circ\text{C}$ for extended temperature variants).

4. What Actually Fails in the Field (Senior Dev Reality Check)

In over a decade of taking Nordic SoCs to production, the silicon gate oxide or transistor logic almost never fails first. The actual reliability bottlenecks that impact field MTBF are almost always:

Flash Exhaustion:
- Writing BLE bonding data, sensor telemetry, or logs to flash too frequently without proper wear-leveling (FDS / LittleFS / Zephyr NVS). If an engineer loops a periodic write directly to NVMC, you will burn through the 10k page endurance in weeks.
$V_{DD}$ Transients and Slew Rate:
- Absolute maximum ratings on $V_{DD}$ are typically $V3.9\text{ V}$ (operating maximum $V3.6\text{ V}$ ). Hot-plugging batteries or poor buck/boost regulator step response can cause overvoltage spikes exceeding abs-max ratings, causing latch-up or permanent degradation.
Decoupling and DC/DC Inductors:
- When enabling the internal DC/DC converter (DCDCEN), component ESR, saturation current of the external high-frequency inductor, and layout parasitics on DCC traces cause ripple and RF degradation.
Solder Fatigue on WLCSP vs. QFN:
- If you are using the ultra-compact WLCSP package in high-vibration or high thermal-cycling environments, underfill is mandatory to avoid micro-crack fractures on ball interconnects. QFN packages are far more forgiving mechanically.
Clock Stability & Drift:
- Using an out-of-spec $kHz32.768\text{ kHz}$ low-frequency crystal without accounting for load capacitance ( $C_L$ ) drift across temperature extremes can cause the BLE peripheral clock to drift beyond the connection-event window, manifesting as pseudo-random connection drops in cold/hot environments.