“Reducing Weight by 40% While Maintaining Robustness for Harsh Environment Operations”

Project Overview

Customer Background

A European UAV manufacturer specializing in industrial surveillance (identity protected) required a weight-optimized RF PCBA for their next-generation drone’s communication module, targeting multi-band operation (900MHz/2.4GHz/5.8GHz). The legacy design’s excessive weight (120g) limited flight time, while inadequate environmental protection caused failures in marine operations.

Technical Challenges

The existing FR4-based 6-layer PCBA (120g, IP54) suffered from:
🔴 Excessive Weight:

• Thick copper layers (2oz) and unnecessary grounding planes
• Bulky 0805/0603 passives limiting miniaturization

🔴 Environmental Weaknesses:

• Corrosion in salty/coastal environments (72h salt spray test failures per MIL-STD-810G)
• Humidity-induced delamination at high-altitude operations

🔴 Inefficient RF Performance:

• Insertion loss spikes (±0.8dB) due to improper microvia transitions
• Limited assembly density preventing PoP (Package-on-Package) integration

KKPCB’s Weight-Saving & High-Reliability Solution

1. Advanced Material & Stackup

• Core Material: Aluminum substrate (AI 6061) + Low-loss PTFE hybrid build-up:
  • Dielectric Constant (ε_r): 3.4 ±0.05 @ 6GHz
  • Thermal Conductivity: 2.2 W/m·K (3× better than FR4)
• Blind/Buried Vias: HDI 1+n+1 stackup, reducing layer count vs. conventional 6-layer
• Final Weight: 72g (40% reduction)

2. IP67 Environmental Protection

• Parylene-based Conformal Coating:
  • Salt Spray Resistance (MIL-STD-810G): 500h no corrosion
  • Humidity Resistance: 95% RH @ 85°C, 1000h stable
• Corrosion-Resistant ENIG Finish (Au: 0.08μm, Ni: 4μm)

3. High-Density Assembly (0402 + PoP)

• Micro-SMT Components: 0402 passives vs. legacy 0603
• 3D PoP Integration: RF SoC + Memory stacked assembly, saving 15% PCB area
• Automated Optical Inspection (AOI) optimized for tiny components

Performance Results

✈ Operational Improvements:

• 22% Increase in UAV Flight Time (from 45 to 55 mins with same battery)
• 18% Lower BOM Cost (via optimized material selection & miniaturization)

📡 RF Performance:

• Insertion Loss Variance: <0.3dB across bands
• VSWR: <1.5:1 at all three communication bands

🔧 Reliability:

• 50G Shock / 10-500Hz Vibration Test Passed (DO-160G)
• Thermal Cycling (-40°C ↔ +85°C): 500 cycles with no failure

Why KKPCB for UAV Electronics?

✅ Lightweighting Experts: RF + Power PCBAs under 100g
✅ Harsh-Environment Specialization: IP67 / MIL-STD-810G qualified
✅ High-Density Assembly: 01005, PoP, uBGA experience

Need a Lighter, Tougher PCBA for Drones?
Contact our UAV solutions team:
📧 [email protected] | 🌍 www.kkpcb.com/uav