08 · WELLEX BAND — Hardware Platform
Screenless biometric wristband, proprietary design · Medical-grade sensors · Free with $19/mo subscription
⚠️ Wellex Band measures biometrics for WVI calculation. WVI determines Target Yield tier — not a guaranteed return.
1. Device Philosophy
Wellex Band is a screenless biometric oracle designed and engineered in-house by Wellex. The absence of a screen ensures maximum battery autonomy (up to 14 days) and absolute focus on data quality. Every measurement is cryptographically signed and transmitted via BLE 5.3 to the Wellex app for WVI calculation → Monthly Yield.
One model. Top-tier specifications. Free with $19/mo subscription.
Data path:
Sensors → TEE (signing) → BLE 5.3 → App → Wellex Oracle → On-chain WVI
2. Technical Specifications
2.1 Key Characteristics
| Parameter | Value |
|---|
| Name | Wellex Band |
| Type | Screenless smart band |
| Development | Wellex (proprietary design, engineering, firmware) |
| Lineup | 1 model (top-spec) |
| Price with subscription | $0 (free) with $19/mo subscription |
| Retail price | $249 (without subscription) |
| SoC | Nordic nRF5340 (dual-core ARM Cortex-M33, 128 + 64 MHz) |
| RAM | 512 KB + 64 KB (network core) |
| Flash | 1 MB + 256 KB |
| Secure Element | Infineon OPTIGA Trust M (TEE, cryptographic key storage) |
| Wireless | BLE 5.3 (LE Audio ready, extended range, direction finding) |
| NFC | Quick pairing (tap-to-pair) |
2.2 Sensor Module
| Sensor | Model / Type | Specification | Application in WVI |
|---|
| PPG | Dual-LED (green 525 nm + red 660 nm) | HR continuous, beat-to-beat RR | WVI core: HRV, stress, recovery |
| ECG | Dry electrodes (touch-based) | Single-lead, on demand | HRV validation, medical grade |
| SpO₂ | Red (660 nm) + IR (940 nm) | Continuous, accuracy ±2% | Recovery, sleep quality |
| EDA | 2 × Ag/AgCl electrodes | SCL + SCR (10 Hz) | 11 emotions, stress |
| Accelerometer | Bosch BMA456 (3-axis) | 50 Hz, ±16g, 12-bit | Steps, calories, sleep staging |
| Gyroscope | Bosch BMI270 (3-axis) | 50 Hz, ±2000 °/s | Workout classification |
| Temperature | TMP117 (Texas Instruments) | Accuracy ±0.1 °C, resolution 0.0078 °C | Circadian rhythm, recovery |
| Barometer | BMP390 (Bosch) | Altitude ±0.5 m | Floors, altitude training |
2.3 Physical Characteristics
| Parameter | Value |
|---|
| Dimensions (capsule) | 42 × 18 × 10.5 mm |
| Weight | 8.5 g (capsule) / 22 g (with strap) |
| Case material | Aerospace-grade polycarbonate + stainless steel (back plate) |
| Water resistance | IP68 (5 ATM / 50 m, swimming) |
| Dust protection | IP6X (full) |
| Operating temperature | −10 °C … +50 °C |
| Strap sizes | S (130–170 mm) · M (155–210 mm) · L (190–240 mm) |
| Colors | Midnight Black · Arctic White · Deep Ocean · Forest Green |
2.4 Battery and Charging
| Parameter | Value |
|---|
| Capacity | 180 mAh (LiPo) |
| Battery life | up to 14 days (screenless — zero display power consumption) |
| Monitoring mode | PPG always-on (1 Hz), Accel 50 Hz, EDA 10 Hz |
| Charging | Magnetic, USB-C pogo pin cradle |
| Full charge cycle | 0 → 100% in 45 min |
| Quick charge | 10 min → 3 days of battery life |
| LED indicator | Tri-color (charging / pairing / OTA) |
2.5 Certifications
| Certification | Status | Description |
|---|
| CE (EU) | ✅ Obtained | Electromagnetic compatibility |
| FCC (US) | ✅ Obtained | Radio frequency compliance |
| Bluetooth SIG | ✅ Qualified | BLE 5.3 |
| IP68 | ✅ Confirmed | Third-party lab tested |
| RoHS | ✅ Compliant | Restriction of hazardous substances |
| FDA 510(k) | 🔄 Roadmap Q4 2026 | Medical device classification |
| MDR (EU) | 🔄 Roadmap 2027 | Medical device regulation |
3. Medical-Grade Accuracy
3.1 Validation
| Metric | Accuracy | Reference |
|---|
| HR (heart rate) | ±2 BPM vs ECG Holter | IEC 60601-2-27 |
| HRV (RMSSD) | r = 0.94 vs ECG | Schäfer & Vagedes, 2013 |
| SpO₂ | ±2% vs pulse oximeter | ISO 80601-2-61 |
| Sleep stages | κ = 0.72 vs PSG | de Zambotti et al., 2019 |
| Steps | ±3% vs manual count | — |
| Temperature | ±0.1 °C vs reference | — |
| ECG | Diagnostic quality (verified by cardiologists) | IEC 60601-2-25 |
3.2 Production Calibration
Every Wellex Band undergoes a full calibration cycle:
- PPG — comparison with golden reference photodiode
- SpO₂ — hypoxic chamber (SaO₂ 70–100%)
- Temperature — climate chamber (15–45 °C)
- Accelerometer — 6-point tumble test
- ECG — synthetic ECG signal verification
- BLE range — minimum 15 m in open field
- Water resistance — pressure chamber (5 ATM, 10 min)
4. Firmware and OTA Updates
4.1 Firmware Architecture
Application Layer
├── Sensor Manager (PPG, EDA, Accel, Gyro, Temp, Baro)
├── Data Buffer (local storage up to 7 days)
├── WVI Pre-processor
└── TEE Signer (cryptographic signing)
BLE Communication Stack
RTOS: Zephyr (nRF Connect SDK)
Hardware Abstraction Layer (HAL)
├── Nordic nRF5340 SoC
└── Infineon OPTIGA Trust M
4.2 OTA Updates (Over-the-Air)
| Parameter | Value |
|---|
| Protocol | Nordic DFU over BLE 5.3 |
| Security | Signed images (Ed25519), verification via Secure Element |
| Update size | 50–200 KB (delta updates) |
| Installation time | 2–5 min |
| Rollback | Dual-bank: on error — automatic rollback to previous version |
| Notification | Push in app: "Firmware v2.2.0 available — improved HRV accuracy" |
| Background download | Downloads in background; installs while charging (> 30%) |
| Frequency | ~once every 6–8 weeks |
4.3 Firmware Roadmap
| Version | Timeline | Changes |
|---|
| v1.0.0 | Q2 2026 | Launch: all sensors, BLE 5.3, TEE |
| v1.1.0 | Q3 2026 | Improved sleep staging algorithm |
| v1.2.0 | Q4 2026 | Advanced emotion detection (EDA + HRV fusion) |
| v2.0.0 | Q1 2027 | ML on-edge: basic WVI pre-processing on chip |
| v2.1.0 | Q2 2027 | LE Audio support, battery optimization |
5. TEE — Trusted Execution Environment
5.1 Components
| Element | Description |
|---|
| Secure Element | Infineon OPTIGA Trust M |
| Keys | Ed25519, generated on-chip, non-extractable |
| Packet signing | {sensor_data, timestamp, nonce, signature} |
| Attestation | Device identity certificate, issued at manufacturing |
| Anti-tamper | Physical tampering detection → key destruction |
5.2 Trusted Data Pipeline
Sensor Reading
→ TEE: sign(data + timestamp + monotonic_nonce)
→ BLE 5.3 encrypted channel
→ App: verify(signature, device_certificate)
→ Cloud: re-verify + WVI calculation
→ Oracle: on-chain WVI commitment (hash)
Guarantee: data cannot be forged on the device, during transmission, or in the app.
6. SDK and Integration
| Platform | Language | Status |
|---|
| iOS | Swift (SwiftUI) | ✅ Production |
| Android | Kotlin (Jetpack Compose) | ✅ Production |
| React Native | TypeScript bridge | ✅ Production |
| Flutter | Dart plugin | ✅ Production |
| Web (test) | Web Bluetooth API | 🔄 Beta |
6.2 SDK Capabilities
| Feature | Description |
|---|
| BLE Management | Scan, connect, disconnect, auto-reconnect, error handling |
| NFC Pairing | Tap-to-pair (iOS 16+, Android 11+) |
| Real-time HR | Streaming heart rate (1 Hz) |
| Beat-to-beat RR | Critical for WVI (every beat) |
| SpO₂ Continuous | Streaming oxygen saturation |
| EDA Stream | SCL + SCR (10 Hz) |
| ECG On-demand | ECG recording on demand (30 s) |
| Raw Accelerometer | 50 Hz, 3 axes |
| Raw Gyroscope | 50 Hz, 3 axes |
| Temperature | 1 Hz |
| Battery & Status | Charge level, firmware version |
| OTA DFU | Programmatic update initiation |
| Data Export | Local buffer → batch export |
6.3 Data Streams
| Stream | Frequency | Format | Application |
|---|
| HR | 1 Hz (continuous) | BPM (uint8) | WVI: exertion, recovery |
| RR intervals | Beat-to-beat | ms (uint16) | WVI: HRV → emotions, stress |
| SpO₂ | 1 Hz | % (uint8) | WVI: recovery, sleep |
| EDA (SCL) | 10 Hz | µS (float32) | 11 emotions |
| EDA (SCR) | Event-based | µS + latency | Stress, arousal |
| ECG | 250 Hz (on demand) | mV (int16) | HRV calibration |
| Accel | 50 Hz | g × 3 axes (int16) | Steps, sleep, activity |
| Gyro | 50 Hz | °/s × 3 axes (int16) | Workout type |
| Temperature | 1 Hz | °C (float16) | Circadian rhythm, recovery |
| Barometer | 1 Hz | hPa (float16) | Altitude, floors |
7. Device Business Model
7.1 Pricing
| Model | Price | Condition |
|---|
| With subscription | $0 (free) | $19/mo subscription (1-year lock-up) |
| Without subscription | $249 | Basic tracking: steps, sleep |
| Warranty replacement | $0 | Within 24 months |
| Post-warranty replacement | $99 | Discounted price |
7.2 $19/mo Subscription Breakdown
| Component | Without Subscription | With Subscription ($19/mo) |
|---|
| Wellex Band | ❌ ($249) | ✅ Free |
| Basic tracking | ✅ | ✅ |
| WVI calculation | ❌ | ✅ |
| Monthly Yield on deposit | ❌ | ✅ |
| AI Coach (video / audio) | ❌ | ✅ |
| 11 emotions | ❌ | ✅ |
| Detailed analytics | ❌ | ✅ |
| Seasonal challenges | ❌ | ✅ |
| NFT badges | ❌ | ✅ |
| Leaderboards | ❌ | ✅ |
| OTA updates | ✅ | ✅ |
7.3 Device Economics
| Metric | Value |
|---|
| Cost of goods (BOM) | ~$38 |
| Manufacturing + QC | ~$12 |
| Logistics | ~$5 |
| MRR per user | $19/mo |
| Device payback period | 3 months |
| At 10,000 subscribers: MRR | $190,000 |
| At 10,000 subscribers: ARR | $2,280,000 |
| Subscription margin | ~85% |
8. Competitive Comparison
| Device | Price | ECG | EDA | SpO₂ | HRV | Screenless | Web3 | Battery |
|---|
| Xiaomi Mi Band 9 | $35 | ❌ | ❌ | ✅ | ❌ | ❌ | ❌ | 16d |
| Fitbit Charge 6 | $160 | ❌ | ✅ | ✅ | ✅ | ❌ | ❌ | 7d |
| Oura Ring Gen 3 | $299 + $6/mo | ❌ | ❌ | ✅ | ✅ | ✅ | ❌ | 7d |
| Whoop 4.0 | $0 + $30/mo | ❌ | ❌ | ✅ | ✅ | ✅ | ❌ | 5d |
| Apple Watch Ultra | $799 | ✅ | ❌ | ✅ | ✅ | ❌ | ❌ | 2d |
| Wellex Band | $0 + $19/mo | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | 14d |
Wellex Band is the only device combining: ECG + EDA + full sensor stack + screenless + Web3 yield + 14-day battery.
9. Manufacturing and Logistics
9.1 Manufacturing Process
| Stage | Description | Timeline |
|---|
| PCB fabrication | 4-layer HDI PCB, Shenzhen | 2 weeks |
| Component sourcing | Nordic, Bosch, TI, Infineon | 4–6 weeks (lead time) |
| SMT assembly | Pick-and-place, reflow | 1 week |
| Module testing | ICT + functional test (100%) | During assembly |
| Encapsulation | Injection molding, IP68 sealing | 1 week |
| Final QC | All sensors + BLE + water test on every device | 2 days |
| Packaging | Branded box, QR → app, strap, charger | 1 day |
| Shipping | DHL Express (global), sea freight (bulk) | 3–14 days |
9.2 Market Launch Timeline
| Phase | Timeline | Description |
|---|
| Engineering Validation (EVT) | Complete | Prototypes, sensor testing |
| Design Validation (DVT) | Q1 2026 | Final design, certifications |
| Production Validation (PVT) | Q1 2026 | Pilot batch of 500 units |
| Mass Production (MP) | Q2 2026 | Mass production start |
| Production capacity | — | 10,000 units/mo (scalable to 50,000) |
10. Hardware Roadmap
| Version | Timeline | Description |
|---|
| v1.0 (Launch) | Q2 2026 | Full sensor stack, BLE 5.3, TEE, IP68 |
| v1.5 (OTA) | Q4 2026 | ML on-edge, improved sleep and emotion algorithms |
| v2.0 | Q2 2027 | UWB (proximity), NFC payments, updated design |
| v3.0 | Q2 2028 | Non-invasive glucose (CGM), eSIM, mmWave BP |
11. Plan B — MVP Without Physical Band
If hardware delivery delays impact launch timeline, Wellex operates in Software-First Mode:
| Mode | Description | WVI Source |
|---|
| Full Hardware | Wellex Band + APP + WEB | Real-time biometrics via band |
| Software-First (Plan B) | APP + WEB, no band required | Manual daily check-in (5 inputs, 60 sec) |
| Partner Device | Compatible third-party wearables (Apple Watch, Garmin, WHOOP) | HealthKit / Google Fit via API |
Software-First WVI calculation:
▸ User inputs mood (1–10) + sleep hours + sleep quality + steps estimate + stress level
▸ WVI calculated from 5 inputs with lower precision (±15 vs ±5 for band)
▸ Clearly marked as "Estimated WVI" in APP — no false precision
▸ Band arrival → automatic switch to full biometric WVI
Partner Device integration (Phase 2, Q4 2026):
▸ Apple Health / Google Fit API → extracts HRV, sleep, activity
▸ WVI calculated from third-party data with standard formula
▸ No TEE anti-cheat — partner device users excluded from highest yield tiers
This ensures zero launch delay regardless of hardware supply chain status.
→ Related documents: 03_WELLNESS_SCORE.md (WVI from band data) · 04_APP_UX.md (mobile app) · 17_TECH_ARCHITECTURE.md (technical architecture)
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