The HD-EFI product series is a micro-miniature interface designed to allow large board tolerance stack ups, blind mating, and multiple RF lines. It is available in common PCB jack and cable plug configurations, with an assortment of bullet adapters to accommodate many board to board spacing options.

The HD-EFI interface is a proprietary design, allowing for a very stable RF signal over the full axial range of the connector system. It has generous “float” to compensate for the axial and radial misalignment tolerance common in small package sized applications.

The interface is available as a 50 Ω connector system with a performance of DC to 6 GHz, making them ideal for high-performance applications with a small package size.


Related Products

HD-EFI Bullets

HD-EFI Adapters


Features and Benefits

  • Available as HD-EFI for DC to 6 GHz 50 Ohm systems
  • Proprietary configuration designed to maximize radial and axial float in board-to-board applications
  • Provides crash-proof mating



  • Wireless Base Station Equipment
  • Multiple Board to Board Connections
  • Complex PCB Stack-ups
  • Mil/Aero
  • Broadband
  • Routers
  • Telecommunications


HD-EFI 50 Ohm Specifications 

Impedance 50 Ω
Frequency Range DC - 6 GHz
Voltage Rating 335 VRMS
Dielectric Withstanding Voltage 1000 VOLTS
Contact Resistance:  
Center Contact 5 mΩ Max. (Initial)
Outer Contact 5 mΩ Max. (Initial)
Insulator Resistance 5000 MΩ Min.
Return Loss/VSWR (Mated Solution):  
Axial Misalignment ± 0.7 mm  
DC - 2 GHz 24 dB (1.14)
2 - 4 GHz 20 dB (1.22)
4 - 6 GHz 16 dB (1.38)
Axial Misalignment ± 0.3 mm  
DC - 2 GHz 28 dB (1.08)
2 - 4 GHz 25 dB (1.12)
4 - 6 GHz 21 dB (1.20)
Insertion Loss (Mated Solution):  
DC - 3 GHz -0.14dB
3 - 6 GHz -0.27dB
Isolation 70dB Min @ Up to 4 GHz @ 8mm Pitch
3rd Order Intermodulation 930 & 955 MHz (2X43 dBm), -163dBc Max (Low PIM Designs)
Power Handling 40 W @ 2.6 GHz @ 95 C Tested
  120 W @ 2.5 GHz @ 95⁰ C Tested
Interface Mating Forces  
Engagement 12 N Max (Smoothe Bore), 25 N Max (Limited Detent)
Disengagement 2 - 6 N (Smooth Bore),  9 N Min (Limited Detent)
Connector Durability 50 Cycles Min. (Limited Detent)
  200 Cycles Min. (Brass Housing) (Smooth Bore)
Center Pin Mating Forces:  
Engagement 3 N Max (Ø 0.52mm Max Pin with Chamfer)
Disengagement 0.2 N Min (Ø 0.48mm Min Pin with Chamfer)
Outer Contact Mating Forces:  
Engagement 8 N Max (Ø 3.52mm Min Hole with Chamfer)
Disengagement 1 N Min (Ø 3.58mm Min Hole with Chamfer)
Mechanical Misalignment:  
Axial ±0.7 mm
Radial ±0.7 mm
Max Floating Angle 5⁰ Surface Mount Parts, 3.5⁰ Through-hole Mount Parts
Min Board to Board Distance 11.46 mm
Temperature Range -45°C To 125°C
Thermal Shock MIL-STD-202, Method 107, condition B
Corrosion Resistance MIL-STD-202, Method 101, condition B
Humidity/Temperature Cycling MIL-STD-202, Method 106, condition A
Temperature Life 250 Hours at 125° C, No Damage to Parts
Vibration MIL-STD-202, Method 204, condition B
Mechanical Shock MIL-STD-202, Method 213, condition A
Body Brass, Gold Plated
Outer Contacts:  
Contact Beryllium Copper, White Bronze Plated
Stamped Version Beryllium Copper, White Bronze Plated
Center Contacts:  
Female Beryllium Copper Heat Treated, Gold Plated
Male Brass, Gold Plated
Stamped Version Copper Alloy, Gold Plated
Bullet POM, Natural
PCB Surface/Through-Hole Mount LCP, Natural
PCB Edge Mount PTFE, Natural
 These characteristics are typical and may not apply to all connectors.

Interface Dimensions

HD-EFI is an Amphenol RF proprietary interface.  Contact us for additional information.