Tailored Dimensions Air Core Coil No Magnetic Saturation Air Coil Inductors Linear Performance Rapid Prototyping

Custom Air Core Inductor Tailored Dimensions No Magnetic Saturation Linear Performance Low MOQ Rapid Prototyping

HALA-CUSTOM-TD: Fully Tailored Air Core Inductor Platform

Why One Size Never Fits All in RF Design

Every RF matching network, bias tee, and filter topology imposes unique constraints on the passive components within it. A 7nH inductor optimized for a 28GHz 5G mmWave beamformer bears little resemblance to a 48nH choke designed for a 1GHz L-band LNB. Yet most inductor catalogs force engineers to select from a handful of fixed values, accepting the design compromises that come with off-the-shelf parts.

The HALA-CUSTOM-TD platform eliminates these compromises by making dimensional customization the default workflow. Building on the proven HALA precision automated winding platform — the same manufacturing technology that produces the field-proven HALA060, HALA080, HALA100, HALA120, and HALA200 series — the CUSTOM-TD variant lets you specify coil diameter, turn count, wire gauge, and inductance value to match your exact circuit requirements.

Tailored Structural Dimensions: The Full Customization Matrix

No Magnetic Saturation: The Air-Core Advantage at the Physics Level

Every ferrite-core inductor exhibits a fundamental failure mode above ~100MHz that no amount of design optimization can fix: magnetic saturation. As DC bias current increases through a ferrite core, the magnetic permeability μᵣ drops, and with it, the inductance collapses — often by 30–80% at rated current. In a GaN PA bias tee carrying 300mA at 28V, a ferrite choke that loses 50% of its inductance drops its RF impedance by half, leaking RF energy into the DC supply and degrading both efficiency and linearity.

The HALA-CUSTOM-TD eliminates this failure mode entirely. With an air core operating at the fundamental free-space permeability μ₀ = 4π * 10⁻⁷ H/m — a universal constant that does not change with current, temperature, or frequency — the inductance-versus-current curve is perfectly linear from 0mA to the maximum rated current. There is no ferrite domain to saturate, no permeability knee to navigate, and no need for bias-dependent inductance derating tables. What you measure at 0mA is exactly what you get at full rated current — a guarantee no ferrite inductor can make.

Low MOQ & Rapid Prototyping: From Concept to Verification in Days

Engineering schedules do not wait for component lead times. The HALA-CUSTOM-TD rapid prototyping service ships evaluation quantities within 5–7 business days of order confirmation, with flexible minimum order quantities starting at 10 pieces. The same precision automated winding, in-line optical inspection, and S2P Touchstone characterization that serve production volumes serve your prototype order — ensuring the performance you measure on the bench is identical to what you will receive in production.

Prototyping deliverables include: evaluation samples (10–100 pieces), S2P Touchstone data (100MHz–26.5GHz, 201 points per file), a datasheet with measured parameters, handling and assembly guidelines, and a Certificate of Conformance.

Key Specifications

Assembly Guidelines

• Perpendicular Mounting: Orient coil axis at 90° to the RF microstrip trace. Parallel alignment creates parasitic mutual inductance that degrades S-parameters and channel isolation. A 15° deviation increases near-field coupling by 2–3dB at 10GHz.
• Minimum Lead Length: Trim leads flush with PCB pad edge after soldering. Each excess millimeter adds ~0.8–1.0nH parasitic series inductance — significant relative to low-nH target values.
• Micro-Soldering: SAC305 lead-free or Sn63/Pb37. Tip temperature ≤260°C, maximum 3-second dwell per joint. The enameled copper wire insulation degrades above ~300°C.
• Post-Solder Fixation: After RF tuning, apply a micro-droplet of low-dielectric RF adhesive (εᵣ < 3.0, tan δ < 0.005) to immobilize the coil geometry. Verify S-parameters post-cure.
• Storage: ESD-safe moisture-barrier packaging at 20–25°C, 40–60% RH. Tinned leads maintain solderability for 1 year from delivery. MSL 1 — unlimited floor life.

FAQ

Q: How many turns do I need for my target inductance?
A: Contact us with your target inductance, frequency band, and current requirement. Our application engineers will recommend the optimal combination of turns, wire gauge, and coil diameter from the HALA platform. For reference: 6T ≈ 7nH, 8T ≈ 11nH, 10T ≈ 14nH, 12T ≈ 17–26nH (wire gauge dependent), 20T ≈ 48nH on the 0.30mm ID platform.

Q: What is the shelf life and recommended storage?
A: 1 year from delivery when stored at 20–25°C and 40–60% RH in original moisture-barrier packaging. The pre-tinned leads maintain full solderability per J-STD-002 criteria under these conditions.

Q: Can I get S2P data for simulation before ordering?
A: S2P Touchstone files (100MHz–26.5GHz, 201 points, 2-port) are provided per production lot. For custom configurations, reference data from similar geometries on the HALA platform is available during the design phase.

Applications

• 5G mmWave Phased-Array Bias Tees: Custom inductance values per element with zero saturation at full array bias current.
• GaN/GaAs Power Amplifier Bias Networks: Tailored choke impedance for 28–50V drain bias at 200–500mA with zero inductance droop.
• SATCOM L/S/C/X/Ku-Band LNBs and BUCs: Per-band optimized inductance values with radiation-immune air-core construction.
• Optical Transceiver Bias Networks (100G/400G/800G): Custom inductance for EML/DML laser bias injection with flat passband across 25–56Gbaud.
• Wideband Test & Measurement Front-Ends: Precision-binned tolerances and per-lot S2P data for calibration-grade designs.

Contact us with your target specifications for a rapid feasibility assessment and quotation. Standard HALA catalog values ship from stock; custom configurations deliver in 1–2 weeks.