From Prototype to Production: Scaling Your IoT Product

Building a prototype that works on your desk is the easy part. Turning it into a manufactured product that works reliably in thousands of units across different environments — that's engineering.

The Production Journey

[Idea] → [Prototype] → [EVT] → [DVT] → [PVT] → [Mass Production]
  1 wk      4 wks       6 wks    4 wks    3 wks     Ongoing

Stage Definitions

| Stage | Goal | Output | |-------|------|--------| | Prototype | Prove the concept works | Breadboard + bodge wires | | EVT (Engineering Validation) | Verify all features on custom PCB | 10-20 units | | DVT (Design Validation) | Test reliability and manufacturability | 50-100 units | | PVT (Production Validation) | Validate manufacturing process | 200-500 units | | MP (Mass Production) | Scale to volume | 1000+ units |

EVT: Your First Real PCB

This is where most startups make critical mistakes. Follow these guidelines:

1. Test all interfaces — Don't assume they work because the datasheet says so
2. Add test points — Every signal you might need to debug
3. Include jumpers — For optional features you might cut
4. Over-spec power — Use bigger capacitors than you think you need
5. Design for hand soldering — You'll be reworking boards constantly

DVT: Design for Reliability

Environmental testing ensures your product survives the real world:

• Temperature cycling — -20°C to +60°C, 100 cycles
• Vibration testing — Random vibration per IEC 60068-2-64
• ESD testing — ±8 kV contact, ±15 kV air discharge
• Drop testing — 1.5m drops on all faces and corners
• Humidity — 85°C, 85% RH for 1000 hours

Certifications

Mandatory

• FCC (USA) / CE (Europe) — RF emissions compliance
• RoHS — Restriction of hazardous substances
• UL/IEC 62368 — Product safety for IT/AV equipment

Recommended

• IP rating — Ingress protection for outdoor devices
• WiFi Alliance — Interoperability certification
• BIS (India) — Bureau of Indian Standards

Supply Chain Management

Bill of Materials (BOM) Optimization

• Reduce unique parts — Each unique part adds sourcing risk
• Avoid single-source components — Always have a second source
• Design for standard packages — 0402, 0603, QFN are cheapest
• Check lead times — Some ICs have 52-week lead times

Cost Breakdown (Typical IoT Device)

| Category | % of COGS | |----------|-----------| | PCB + Assembly | 25% | | Components | 40% | | Enclosure | 15% | | Packaging | 5% | | Testing + QC | 10% | | Logistics | 5% |

Manufacturing Partner Selection

What to look for in a contract manufacturer (CM):

1. MOQ flexibility — Start with 500-1000 units
2. In-house SMT — Pick-and-place, reflow, and automated optical inspection
3. Testing capability — Functional test jig development
4. Quality certifications — ISO 9001 minimum
5. Communication — Weekly updates and transparent reporting

Common Pitfalls

• ❌ Skipping EVT and going straight to production tooling
• ❌ Not testing with production firmware on production hardware
• ❌ Ignoring regulatory requirements until the end
• ❌ Using hobbyist-grade components in production designs
• ❌ Not budgeting for 15-20% component waste during assembly

Learn the complete product development lifecycle in our Hardware Design & PCB track.