Rogers AD250C PCB: Complete Guide to Specs, Applications & Design Tips

If you’ve been designing RF or microwave circuits for base station antennas, you’ve probably heard about the AD250C laminate. As a PCB engineer who’s worked with dozens of high-frequency materials over the years, I can tell you that AD250C strikes an impressive balance between performance and cost—something that’s hard to find in PTFE-based materials.

This guide covers everything you need to know about Rogers AD250C: from its technical specifications and real-world applications to practical design tips that’ll save you headaches during fabrication. Whether you’re evaluating AD250C for your next antenna project or comparing it against alternatives like RO4350B, you’ll find the answers here.

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What is Rogers AD250C?

Rogers AD250C is a third-generation PTFE/woven fiberglass/ceramic-filled laminate material designed specifically for microwave and RF printed circuit boards. Originally developed by Arlon (now part of Rogers Corporation), AD250C belongs to the AD Series™ antenna materials family.

What makes AD250C stand out is its composite architecture. It combines:

• PTFE (Polytetrafluoroethylene) for excellent electrical properties
• Woven glass reinforcement for mechanical stability and easier processing
• Micro-dispersed ceramic fillers for controlled dielectric constant and thermal stability

This combination delivers low-loss performance (Df = 0.0013 at 10 GHz), tight dielectric constant control (Dk = 2.50 ± 0.04), and excellent passive intermodulation (PIM) characteristics—all at a price point that undercuts many traditional PTFE laminates.

The material was engineered with telecom infrastructure in mind, particularly base station antenna applications where consistent RF performance across temperature cycles is critical.

AD250C Material History

AD250C represents the third generation of commercial PTFE-based RF laminates in the AD Series. Originally developed by Arlon Materials for Electronics (a pioneer in high-frequency laminates since 1958), the AD Series became part of Rogers Corporation’s portfolio in 2015 when Rogers acquired Arlon’s printed circuit board division. This acquisition combined Arlon’s PTFE expertise with Rogers’ global manufacturing and distribution capabilities, making materials like AD250C more accessible worldwide.

The “AD” designation stands for “Advanced Dielectric,” reflecting the material’s position as a premium substrate for demanding antenna applications. Over the years, Arlon and Rogers engineers refined the ceramic filler formulation and glass weave structure to optimize the balance between electrical performance, mechanical stability, and manufacturability.

AD250C Key Technical Specifications

Here’s the complete specification table pulled directly from the Rogers datasheet. I’ve organized it by property type so you can quickly find what you need:

Electrical Properties

Property	AD250C Value	Units	Test Conditions
Dielectric Constant (Process)	2.52	–	23°C @ 50% RH, 10 GHz
Dielectric Constant (Design)	2.50	–	C-24/23/50, 10 GHz
Dissipation Factor (Df)	0.0013	–	23°C @ 50% RH, 10 GHz
Thermal Coefficient of Dk	-117	ppm/°C	0 to 100°C, 10 GHz
Volume Resistivity	4.8 × 10⁸	MΩ-cm	C96/35/90
Surface Resistivity	4.1 × 10⁷	MΩ	C96/35/90
Dielectric Strength	979	V/mil	IPC TM-650 2.5.6.2
PIM Performance	-159 / -163	dBc	43 dBm at 1900 MHz

Thermal Properties

Property	AD250C Value	Units	Test Method
Decomposition Temperature (Td)	>500	°C	5% weight loss
CTE – X axis	47	ppm/°C	-55°C to 288°C
CTE – Y axis	29	ppm/°C	-55°C to 288°C
CTE – Z axis	196	ppm/°C	-55°C to 288°C
Thermal Conductivity	0.33	W/(m·K)	Z-direction
Time to Delamination	>60	minutes	288°C

Mechanical & Physical Properties

Property	AD250C Value	Units
Copper Peel Strength	2.6 N/mm (14.8 lbs/in)	35 μm foil @ 288°C
Flexural Strength (MD/CMD)	60.7 / 44.1	MPa
Moisture Absorption	0.04	%
Density	2.28	g/cm³
Flammability	V-0	UL 94
Dimensional Stability	0.02 / 0.06	mils/inch

Available Thicknesses and Panel Sizes

Standard Thicknesses	Tolerance	Panel Sizes
0.020″ (0.508 mm)	± 0.002″	18″ × 12″, 18″ × 24″
0.030″ (0.762 mm)	± 0.002″	12″ × 18″, 24″ × 18″
0.060″ (1.524 mm)	± 0.003″	12″ × 18″, 24″ × 18″

Copper cladding options: ½ oz (18 μm) and 1 oz (35 μm) electrodeposited or reverse-treated ED copper foil.

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Why Choose AD250C? Key Benefits

After working with AD250C on multiple antenna projects, here’s what I appreciate most about this material:

Low Signal Loss at High Frequencies

With a dissipation factor of just 0.0013 at 10 GHz, AD250C minimizes insertion loss in your RF traces. For antenna feed networks operating in the 1.7–2.7 GHz cellular bands, this translates to higher antenna efficiency and better overall system performance.

Excellent PIM Performance

AD250C achieves PIM values as low as -163 dBc when using S1 copper foil. This is crucial for multi-carrier base station antennas where passive intermodulation can cause interference between channels. The low-profile reverse-treated ED copper option further reduces both PIM and conductive losses.

Tight Dielectric Constant Tolerance

The ±0.04 tolerance on dielectric constant (Dk = 2.50) means you can design impedance-controlled traces with confidence. Unlike materials with ±0.10 or larger Dk tolerances, AD250C gives you the repeatability needed for production quantities.

Cost-Effective PTFE Alternative

Let’s be honest—PTFE materials can get expensive. AD250C was specifically designed as a cost-effective option for commercial telecom applications. It delivers PTFE-level RF performance without the premium pricing of materials like RT/duroid 5880 or RO3003.

Standard PCB Process Compatibility

AD250C is compatible with standard PTFE fabrication processes. You don’t need specialized plasma treatment or sodium etch for adhesion—the woven glass reinforcement and ceramic fillers make it easier to drill, plate, and laminate compared to pure PTFE materials.

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AD250C Applications in RF and Antenna Design

AD250C was engineered specifically for antenna applications. Based on my experience and industry use cases, here are the primary applications:

Cellular Infrastructure Antennas

This is where AD250C really shines. Base station antenna feed networks, corporate feed structures, and patch antenna elements commonly use AD250C. The material handles the wide frequency range from 700 MHz to 2.7 GHz that modern LTE/5G antennas require.

Commercial Satellite Radio Antennas

SDARS (Satellite Digital Audio Radio Service) and GPS antenna systems benefit from AD250C’s stable electrical properties and weather resistance.

Automotive Telematics

V2X (vehicle-to-everything) communication antennas, GPS modules, and connected car systems increasingly rely on AD250C for its thermal stability during harsh automotive operating conditions.

Digital Audio Broadcasting (DAB)

DAB antenna systems in the 174–240 MHz and 1452–1492 MHz bands use AD250C for its low loss and consistent performance.

Radar Feed Networks

While not as common as antenna applications, AD250C sees use in radar manifold and feed network designs where cost optimization is important.

5G Infrastructure

With the rollout of 5G networks, massive MIMO antenna arrays require low-loss, high-consistency materials for their complex feed structures. AD250C’s tight Dk tolerance ensures phase matching across multiple antenna elements—critical for beamforming performance. Many 5G macro cell antennas operating in sub-6 GHz bands use AD250C for their corporate feed networks.

IoT and M2M Antennas

The Internet of Things explosion has created demand for cost-effective antenna materials. AD250C fits well for industrial IoT gateways, smart city infrastructure, and machine-to-machine communication devices where RF performance matters but budgets are constrained.

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AD250C vs Other Rogers Materials: A Practical Comparison

Choosing between Rogers laminates can be confusing. Here’s a side-by-side comparison of AD250C with other commonly considered materials:

Property	AD250C	AD255C	RO4350B	RO4003C
Dielectric Constant (Dk)	2.50	2.55	3.48	3.38
Dissipation Factor (Df)	0.0013	0.0013	0.0037	0.0027
Material Type	PTFE/Glass/Ceramic	PTFE/Glass/Ceramic	Hydrocarbon/Ceramic	Hydrocarbon/Ceramic
CTE-Z (ppm/°C)	196	196	32	46
Processing	PTFE-compatible	PTFE-compatible	FR-4 compatible	FR-4 compatible
Typical Cost	Medium	Medium	Lower	Lower
Best For	Antennas, Low PIM	Antennas	General RF, Power	Low-loss RF

When to Choose AD250C Over RO4350B

Choose AD250C when:

• Ultra-low loss is your priority (0.0013 vs 0.0037 Df)
• You need excellent PIM performance for multi-carrier systems
• Your design requires lower Dk for wider trace geometries
• Antenna efficiency is critical

Choose RO4350B when:

• FR-4 processing compatibility is important
• You need lower Z-axis CTE for multilayer reliability
• Cost is your primary concern
• General RF applications below 5 GHz

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PCB Design Tips for AD250C

Here are practical design guidelines I’ve learned from working with AD250C:

Drilling Considerations

AD250C’s PTFE content means it behaves differently from FR-4 during drilling. Use carbide drill bits designed for PTFE materials. For hole sizes below 0.3 mm, consider laser drilling to avoid excessive burring. Run drilling at slower feed rates than you’d use for epoxy laminates.

Via Plating Preparation

While AD250C doesn’t require sodium etch like pure PTFE, proper surface preparation before electroless copper plating remains important. Most fabricators use plasma treatment to improve copper adhesion on the hole walls. Confirm your fab house has PTFE processing experience.

Impedance Control

When calculating trace widths for 50Ω microstrip lines, use the design Dk of 2.50 (not the process Dk of 2.52). The design value accounts for the actual RF field distribution in your finished circuit. For 0.030″ thick AD250C with 1 oz copper, expect approximately 4.2 mm trace width for 50Ω characteristic impedance.

Hybrid Stackups

AD250C works well in hybrid multilayer constructions where you combine it with FR-4 for non-critical layers. Use appropriate bonding materials—Rogers CuClad or FastRise bondply are good options. Pay attention to CTE matching to prevent delamination during thermal cycling.

Thermal Management

With thermal conductivity of only 0.33 W/(m·K), AD250C isn’t ideal for high-power applications requiring significant heat dissipation. For power amplifier substrates, consider hybrid constructions with metal-backed cores or use higher thermal conductivity materials like RO4835T.

Copper Foil Selection

For antenna applications where PIM is critical, always specify the reverse-treated (RT) ED copper option. Standard ED copper works fine for less demanding applications. The RT foil provides a smoother copper-dielectric interface that reduces both PIM and conductor loss.

Surface Finish Selection

For AD250C boards, ENIG (Electroless Nickel Immersion Gold) works well for most antenna applications requiring wire bonding or where oxidation resistance matters. If cost is a concern and the application allows it, OSP (Organic Solderability Preservative) or immersion tin are alternatives. Avoid HASL (Hot Air Solder Leveling) if you need tight planarity for antenna patches—the uneven surface can affect pattern performance.

Ground Plane Considerations

When designing microstrip antenna elements on AD250C, ensure your ground plane is solid and continuous beneath the radiating patches. Any slots, gaps, or via stitching patterns in the ground can affect antenna characteristics. For feed networks, use adequate via stitching along the edges of coplanar waveguide or grounded coplanar structures to prevent unwanted mode propagation.

Environmental Considerations

AD250C has excellent moisture absorption at just 0.04%—significantly lower than FR-4’s typical 0.15-0.20%. This makes it suitable for outdoor antenna applications. However, for deployments in extreme humidity or direct weather exposure, consider conformal coating or proper radome design to protect the assembled PCB.

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Working with PCB Fabricators

A few tips when ordering AD250C boards:

1. Confirm material availability — AD250C isn’t stocked everywhere. Verify your fabricator has it in inventory or can source it within your lead time.
2. Provide complete specifications — Include the exact Rogers material designation, thickness, copper weight, and any surface finish requirements in your documentation.
3. Discuss stackup early — For multilayer designs, collaborate with your fabricator on the stackup design. They may have specific prepreg or bonding material recommendations.
4. Request impedance coupons — For production quantities, ask for impedance test coupons to verify your trace geometries are achieving target impedance values.
5. Factor in longer lead times — Specialty materials like AD250C typically have longer lead times than standard FR-4. Plan accordingly.

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Useful Resources and Downloads

Here are the essential resources for working with AD250C:

Official Rogers Documentation

• AD Series Data Sheet (PDF) — Complete specifications for AD250C, AD255C, AD300D, and AD350A
• Rogers Laminate Properties Tool — Interactive comparison of all Rogers laminates
• Rogers Corporation Main Site — Product page with sample requests

Design Tools

• Rogers MWI Calculator — Microstrip and stripline impedance calculator optimized for Rogers materials
• Altium Material Library — Includes AD250C material parameters for stackup design

Technical Standards

• IPC-4103 — Specification for base materials for high-speed/high-frequency applications
• IPC-6012 — Qualification and performance specification for rigid PCBs

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Frequently Asked Questions

What is the dielectric constant of AD250C?

AD250C has a process dielectric constant (Dk) of 2.52 and a design dielectric constant of 2.50, both measured at 10 GHz. The design value accounts for the actual microstrip field distribution. Use Dk = 2.50 for your impedance calculations.

Is AD250C compatible with lead-free soldering?

Yes. AD250C has a decomposition temperature (Td) exceeding 500°C and time-to-delamination greater than 60 minutes at 288°C. It easily withstands lead-free reflow profiles with peak temperatures around 260°C.

What’s the difference between AD250C and AD255C?

Both materials share similar loss characteristics (Df = 0.0013), but AD255C has a slightly higher dielectric constant (2.55 vs 2.50). AD255C also offers more thickness options including 0.040″ and 0.125″ versions. Choose based on your required Dk and available thicknesses.

Can AD250C be used in multilayer PCBs?

Absolutely. AD250C is commonly used in multilayer constructions for antenna feed networks. Its low Z-axis thermal expansion (compared to pure PTFE materials) improves plated through-hole reliability. Use compatible bonding materials and work with a fabricator experienced in PTFE multilayer processing.

How does AD250C compare to FR-4 for RF applications?

AD250C significantly outperforms FR-4 at high frequencies. At 10 GHz, AD250C’s dissipation factor (0.0013) is roughly 15× lower than FR-4 (~0.020). AD250C also provides tighter Dk tolerance and much lower moisture absorption. For any application above 1 GHz where loss matters, AD250C is the better choice.

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Conclusion

Rogers AD250C occupies a valuable niche in the RF laminate landscape. It delivers PTFE-level electrical performance with better processability and lower cost than many traditional microwave materials. For base station antennas, commercial wireless systems, and other telecom infrastructure applications, AD250C provides the right balance of low loss, excellent PIM, and practical manufacturing.

The key is understanding where AD250C fits in your design requirements. If ultra-low loss and PIM performance are priorities—and you can accommodate PTFE-style fabrication processes—AD250C deserves serious consideration. For general RF work where FR-4 process compatibility matters more, the RO4000 series remains a strong alternative.

Whatever direction you choose, I hope this guide helps you make an informed decision. Feel free to consult the Rogers technical resources linked above, and don’t hesitate to engage with your PCB fabrication partner early in the design process.