What are HSL/high-speed link connectors? 

By Amy Goetzman | May 21, 2024

Meet the Connector: HSL/High-Speed Link Connectors

What are HSL/high-speed link connectors? 

HSL/High-speed link connectors are used to facilitate high-speed data communication between different components within electronic systems, such as computers, servers, telecommunications equipment, and other digital devices. The term HSL refers to a broad category of high-speed, high-performance interconnects that are capable of supporting data rates that can reach multiple gigabits per second, making them suitable for applications requiring rapid data exchange.

HSL connectors are typically compact, allowing for high-density connections on circuit boards, which is crucial in space-constrained applications. They are engineered to maintain signal integrity over high frequencies and minimize signal degradation and electromagnetic interference (EMI), which are critical factors at high data transfer rates. This involves reducing crosstalk, insertion loss, and return loss, which are common issues at high speeds.

ATTEND’s QSFP Cage 2x2 Press Fit Type w/Connector

ATTEND’s QSFP Cage 2×2 Press Fit Type w/Connector is a small form-factor pluggable (SFP), compact, hot-pluggable network interface module used for telecommunication and data communication applications. ATTEND offers a variety of SFP/SFP+/QSFP cage types that support 1 Gb/s to 40 Gb/s data rates for Gigabit Ethernet, optical applications, and SFP/ SFP+/ QSFP modules for high-speed networking. Design Notes

Design Notes 

Standardization. Several high-speed, high-performance standards, including PCIe, SFP+, and QSFP products, fall into the HSL category. Commonly used standardized HSLs include:

SFP+ (Small Form-factor Pluggable Plus): Used in networking equipment like switches, routers, and network interface cards (NICs). SFP+ products support data rates up to 10 Gb/s. They are hot-swappable and typically used for optical transceivers or direct attach cables.

QSFP (Quad Small Form-factor Pluggable): Used in data centers and high-performance computing networks, QSFPs support higher data rates (up to 100 Gb/s) by combining multiple SFP lanes. They are hot-swappable and used for both optical and copper connections.

PCIe (Peripheral Component Interconnect Express): Used for internal computer connections such as GPU, SSDs, and network and internal expansion cards. PCIe connectors feature high data transfer rates, scalable architecture, and multiple lanes (x1, x4, x8, x16).

HDMI (High-Definition Multimedia Interface): Used for consumer electronics like TVs, gaming consoles, and computers to transmit uncompressed video and audio and support high-definition and ultra-high-definition resolutions, including Ethernet data connection.

USB (Universal Serial Bus): Common connections for peripherals. Successive versions like USB 3.0, USB 3.1, USB 3.2, and USB4 support progressively higher data rates.

Thunderbolt: High-speed connections for peripherals and display; combines PCIe and DisplayPort protocols, supports data, video, and power through a single cable, high data transfer rates (up to 40 Gb/s in Thunderbolt 3 and 4).

Samtec’s Q Pairs® Differential Pair Mezzanine connectors are designed for high-speed, board-to-board applications where signal integrity is essential. Performance of up to 10.5 GHz / 21 Gb/s. Shown here: 0.50 mm Q Pairs® High-Speed Ground Plane Socket Strip.

Samtec’s Q Pairs® Differential Pair Mezzanine connectors are designed for high-speed, board-to-board applications where signal integrity is essential. Performance of up to 10.5 GHz / 21 Gb/s. Shown here: 0.50 mm Q Pairs® High-Speed Ground Plane Socket Strip.

Mounting type or types. Depending on the application and connector type, may include BTB, through-hole, edge mount, and mezzanine mounting.

Durability. HSL connectors are made to withstand frequent connect and disconnect cycles, ensuring reliable performance over the lifespan of the equipment.

Physical properties. HSL connectors come in various sizes, from compact designs for space-constrained applications to larger connectors for more robust connections.

Environmental properties. Specifying the correct HSL depends on the application and operating environment. Ruggedized, sealed, and heavy duty options are available.

Electrical properties

High-speed connectors support data rates from a few gigabits per second (Gb/s) to over 100 Gb/s, depending on the application. Specific properties relating to data transfer rate, signal integrity, insertion loss, impedance, voltage and power handling differ depending on the application and the HSL specified.

Tarng Yu’s new high-speed cable connector solution

Tarng Yu’s new high-speed cable connector solution follows PCIe 5.0 and future PCIe 6.0 Spec requirements for high-speed connections in data centers, servers, and storage units.

Markets and Applications 

  • Automotive
  • Consumer
  • Datacom/Telecom
  • Industrial

HSLs are used in networking equipment (routers, switches, and servers); high-performance computing environments (data centers, where they connect servers, storage systems, and networking devices); industrial automation systems; automotive electronics (advanced driver assistance systems, in-vehicle infotainment, and autonomous driving); high-end consumer electronics (gaming consoles, high-definition video devices, and personal computers), and other applications where high-speed data transfer is essential.


HSLs are available in many variations from many suppliers, including Advanced Interconnections, AirBorn, Amphenol Aerospace, Amphenol Industrial Operations,  Amphenol LTW, Amphenol Pcd, AirBorn, Allied Electronics & Automation, Arrow, Attend, Avnet, Axon’ Cable, Bel Magnetic Solutions, binder, BizLink, Bulgin Components, Carlisle Interconnect Technologies, CDM Electronics Inc., Cinch Connectivity Solutions, COAX Connectors, DigiKey Electronics, EDAC, ept connectors, Fischer Connectors, GreeneTweedHARTING, Harwin, Heilind, Hirose Electric, IMS, I-PEX, ITT Cannon, JAE, JPC Connectivity, KYOCERA AVX, Lumberg, METZ CONNECT, Mouser Electronics, Nicomatic, NorComp, Omnetics Connector Corporation, PEI Genesis, Phoenix Contact, Positronic, Powell Electronics, Preci-Dip, Radiall, RS, Sager Electronics, Samtec Inc., SCHURTER, Smiths Interconnect, SV Microwave, Tarng Yu Enterprise, TE Connectivity, Teledyne Reynolds, Times Microwave Systems, Trexon, TTI Inc., WAGO, Waytek, Weidmüller, and Würth Electronik.

Related products

  • Board-to-board connectors
  • Cable-to-board connectors
  • Mezzanine connectors
  • QSFPs
  • PCIe
  • SFP+

Like this article? Check out our other Meet the Connector and Board-to-Board articles, our Automotive Market Page, and our 2024 Article Archives

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Amy Goetzman
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