1. Customer Profile

Client: Anonymous
Industry: Telecom Infrastructure, 5G Macro/Micro Base Stations
Application: Power Amplifier (PA) Modules + RF Front-End PCBs

High-power base station equipment requiring PCBs are able to handle:

• High current (30A+) for PAs
• Low-loss RF (3.5GHz-28GHz for 5G)
• Thermal stability (85°C ambient, 125°C local hotspots)

Key Challenges Faced:

• Delamination risk from mixed thick-copper (6oz) and RF layers.
• EMI coupling between power and RF sections.
• Thermal warping under high thermal cycling.

2. KKPCB’s Hybrid Power+RF PCB Solution

(A) Material Selection & Stackup

Layer	Material	Function	Key Specs
L1-2	Rogers RO4350B	RF Signal (28GHz mmWave)	Dk=3.66, Df=0.0037 @ 10GHz
L3-4	IT-180A (6oz Cu)	High-Current DC Power	175µm Cu, 10A/mm² current density
L5-6	Isola FR408HR	Digital Control / Mixed Signal	Tg=180°C for thermal stability

Hybrid Bonding:

• Plated slots for low-inductance power-ground connections.
• Buried copper coin heatsinks under GaN transistors.

(B) Critical Design Features

✅ Ultra-Low RF Loss: 0.4dB/inch @ 28GHz (vs. 1.2dB in standard FR4).
✅ Power Integrity: <5mV ripple under 30A dynamic load.
✅ Thermal Management: 3W/mK thermal vias under PAs (reduce hotspot ΔT by 25%).
✅ EMI Shielding: Copper-filled via fences between RF and power sections.

3. Performance Results vs. Competitors

Parameter	Old PCB	KKPCB’s Solution	Improvement
Insertion Loss (28GHz)	1.1dB/inch	0.4dB/inch	64% ↓
Max Current (Continuous)	20A	35A	75% ↑
Thermal Resistance (PA Zone)	12°C/W	7°C/W	42% ↓
Production Yield	82%	98%	16% ↑

Field Test (5G Base Station):

• 40% Longer MTBF (Mean Time Between Failures) vs. previous supplier.
• Passed MIL-STD-810G vibration/shock tests for outdoor deployments.

4. Key Technical Differentiators

▶ Hybrid Material Bonding Technology

• No delamination after 1000x thermal cycles (-55°C to +125°C).
• CTE-matched dielectrics prevent warping in multilayer stack.

▶ Custom RF-Power Via Design

• Symmetrical star vias for low-impedance DC distribution.
• Conical laser vias (60μm) for mmWave RF transitions.

▶ Design Support

• Provided EMI/thermal simulation reports (ANSYS HFSS & Icepak).

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5. Visual Highlights

(A) Hybrid PCB Cross-Section

Layer 1-2: RF (Rogers) 
Layer 3-4: Power (6oz Cu + Thermal Pads) 
Layer 5-6: Control (FR408HR)  ↓ **Copper Coin Heatsink**

Figure: Optimized stackup for 5G PA modules.

(B) Thermal Imaging (Before vs. After)

Left: Competitor PCB (hotspot = 128°C). Right: KKPCB (hotspot = 95°C).

6. Why Chose KKPCB?

✔ Base Station Specialists: 50+ macrocell/small-cell PCB projects since 2018.
✔ Fast Prototyping: 15-day lead time for 12L hybrid prototypes.
✔ Compliance: IPC-6012 Class 3, IATF 16949 (for automotive-grade reliability).

For Your Next Base Station PCB:
➔ Request a Free Hybrid Stackup Design (Email: [email protected]).