The nRF51822-QFAA-R may appear on an existing wireless product's BOM, but “nRF51822” alone is not enough to approve a purchase. Memory variant, firmware compatibility and the complete supplied ordering code all matter.

View the nRF51822-QFAA-R product and inquiry page. Availability and delivery require a specific quotation.

1. QFAA means 256 KB Flash and 16 KB RAM

Nordic's revision and variant table identifies QFAA as a QFN48 device with 256 KB Flash and 16 KB RAM. Do not apply the nRF51822 family's larger RAM options to this variant. The QFN48 package is 6 × 6 mm. The processor is a 16 MHz Arm Cortex-M0. See Nordic's variant table and official product overview.

The 16 KB RAM budget is particularly important. Protocol-stack reservations, application data, buffers, heap and stack must all fit the actual configuration. Nominal chip capacity is not the amount freely available to application code.

2. BLE and proprietary 2.4 GHz are different choices

Nordic positions the device for Bluetooth Low Energy and proprietary 2.4 GHz applications. Sharing a radio band does not make a proprietary protocol compatible with a phone's BLE interface. A phone connection requires suitable BLE firmware, services and application behavior.

Do not describe the proprietary 2 Mbps radio mode as Bluetooth LE 2M PHY support. Nordic explicitly distinguishes those modes. For Bluetooth version and feature claims, verify the selected SoftDevice and its supported features rather than assigning every newer Bluetooth feature to the chip. See Nordic's explanation of proprietary mode versus BLE throughput.

3. Existing products: preserve the working software baseline

Before replenishing an established design, record the approved chip revision or build-code requirements, SDK, SoftDevice, compiler, bootloader and application versions. Check the official compatibility information and relevant errata for the intended combination.

A sample that programs successfully has not yet demonstrated application compatibility. Test advertising, connection establishment, data exchange, reconnect behavior and any firmware-update process used by the product. Include the actual phones or gateways expected in service.

If the supplier proposes QFAC, QFAB, another package or a different complete ordering code, obtain engineering approval. A similar name or more memory does not establish a validated replacement.

4. Is it suitable for a new project?

Start with the feature budget: message size, connection behavior, memory use, update strategy, power target and expected maintenance period. A small existing BLE application and a new feature-rich connected product have different requirements.

Do not select solely on chip price. Compare development effort, available tools and documented support for the required features. If evaluating a newer Nordic family, treat migration as a hardware and software project rather than assuming a drop-in replacement. Our nRF52840 selection guide offers a separate requirements checklist, not a substitution approval.

5. Measure power on the complete product

Battery life depends on advertising and connection settings, payloads, retries, sensor consumption and the power supply. Measure the real board with the intended firmware over a representative operating cycle.

Record both average consumption and peak behavior. A low sleep-current reading alone cannot establish battery life or show that the supply can handle radio activity. Compare samples using the same firmware, battery conditions and radio environment.

6. What should incoming and sample checks include?

  • Match the complete model, packing and shipment documentation to the order.

  • Confirm the silicon variant and any approved revision requirements using appropriate engineering methods.

  • Program the approved firmware and run representative connection and recovery tests.

  • Test memory-sensitive features, including updates if the product supports them.

  • Retain board, firmware, configuration and test-condition records.

A label quantity is not confirmed saleable inventory. A photograph, readable marking or successful connection alone does not prove authenticity or complete performance. Obscured codes should not be guessed; request the agreed traceability information.

7. RFQ checklist

Specify nRF51822-QFAA-R exactly as required by the BOM, and ask the supplier to confirm the manufacturer's complete order code and packing. Do not silently substitute an R7 listing or infer reel size from a shortened suffix.

  • Sample and production quantities.

  • Target arrival date and destination.

  • Packing, lot and documentation requirements.

  • Engineering-approved revision restrictions, where applicable.

  • Agreed acceptance checks and no substitutions without approval.

Submit the details through the WOMAiELEC product page. Price, quantity and lead time are subject to confirmation; no stock or authenticity guarantee is inferred from packaging photographs.