OpenGMSL Explained: In-Vehicle Connectivity for ADAS and Infotainment

OpenGMSL is an open standard for the high-speed serial links that carry video and sensor data inside a car: from cameras to the ADAS computer, and from the infotainment processor to displays. It opens up Analog Devices' Gigabit Multimedia Serial Link (GMSL) technology, already used in many production vehicles, so that other chip makers can build compatible parts. The goal is a multi-vendor supply chain for one of the busiest data paths in a modern vehicle.

In the automotive world things are moving fast. As cars get smarter and more connected, the need for high-speed, reliable in-vehicle connectivity keeps rising. OpenGMSL is the newest entrant among the standards competing for that role. This post explains what OpenGMSL is, how it works, its key features, and how it compares with the other standards.

Key takeaways

• OpenGMSL is an open, association-managed standard built on ADI's GMSL serialiser/deserialiser (SerDes) technology.
• It targets camera, sensor and display links for ADAS, autonomous driving and infotainment, with reported rates up to 12 Gbps per link.
• Its main rivals are MIPI A-PHY, ASA Motion Link, TI's proprietary FPD-Link, standards emerging from China, and, for networking rather than raw video, automotive Ethernet.
• The selling point is a large installed base plus a path to second-source compatible chips.
• Link choice is driven by sensor bandwidth, cable reach, latency, functional safety and supply-chain strategy.

What is OpenGMSL?

OpenGMSL is an open standard designed to simplify high-definition video and sensor data connectivity in vehicles. It is managed by the OpenGMSL Association, a non-profit body whose formation was announced in 2025, and it builds on the success of GMSL technology to push forward autonomous driving, ADAS and infotainment systems.

GMSL itself has been in cars for well over a decade. Until now, if a car maker designed in GMSL, the serialiser and deserialiser chips came from ADI (which acquired the technology with Maxim Integrated). Opening the specification lets other silicon vendors build interoperable parts, which is what car makers and Tier-1 suppliers usually want before committing a platform for many years.

How a GMSL-style link works

A camera or display link of this kind is an asymmetric point-to-point SerDes connection:

1. Serialiser. At the camera, a serialiser chip takes the image sensor's parallel or MIPI CSI-2 output and turns it into a single high-speed serial stream.
2. Cable. The stream travels over a single coaxial cable or a shielded twisted pair, typically several metres long and up to about 15 m in a large vehicle.
3. Deserialiser. At the ADAS computer or zone controller, a deserialiser recovers the data and hands it to the SoC, again usually as CSI-2.
4. Back channel. A much slower reverse channel on the same cable carries control traffic such as I2C register writes to configure the camera.
5. Power over coax. The same cable can also carry DC power to the camera, so one connector does everything.

The asymmetry matters: a camera sends gigabits per second but only needs to receive a few megabits of control data. Earlier GMSL generations reflect this, with GMSL2 commonly quoted at 6 Gbps forward and 187.5 Mbps reverse, and GMSL3 at 12 Gbps forward.

Key features and benefits

• High-resolution video. OpenGMSL supports high-resolution digital video transmission, so cameras, computers and displays work together smoothly. It is aimed squarely at advanced vision systems and infotainment.
• An open, collaborative model. The standard invites car makers, suppliers and technology companies to work together, which strengthens the supply chain, cuts costs and shortens time to market.
• Proven technology. Built on established GMSL technology, OpenGMSL starts with a large, working ecosystem, which gives confidence that it will perform in real automotive applications.
• Designed for what comes next. It is intended to support next-generation autonomous and connected vehicles, with the aim of making cars safer, more immersive and more personalised.

A worked bandwidth example

Why do these links need many gigabits per second? Take an 8 MP front camera (3840 x 2160 pixels) sending 12-bit RAW data:

• At 30 frames per second: 3840 x 2160 x 12 x 30 = about 2.99 Gbps of pixel data.
• At 60 frames per second: about 5.97 Gbps.

Add blanking, protocol overhead and any embedded metadata, and the 60 fps case no longer fits comfortably in a 6 Gbps link. That is the class of camera that pushes designs towards 12 Gbps links. A 1920 x 720 cluster display at 24 bits per pixel and 60 Hz needs about 2 Gbps, while larger pillar-to-pillar displays need several times that.

Competing standards

OpenGMSL is not the only player. These are the other standards in the automotive connectivity space:

• MIPI A-PHY. Created by the MIPI Alliance, this open standard is designed for high-speed, long-reach data transmission in cars and is well suited to ADAS and infotainment. It was also adopted by the IEEE as IEEE 2977.
• ASA Motion Link (ASA-ML). From the Automotive SerDes Alliance, ASA-ML is another open standard for ADAS, autonomous driving and infotainment links.
• Automotive Ethernet. Known for high bandwidth and low latency, automotive Ethernet is widely used for in-vehicle networking. It supports many applications but can be more complex and costly to implement for a raw camera stream.
• Standards from China. China is developing its own automotive connectivity standards to support its fast-growing vehicle market. They aim to provide high-performance, cost-effective solutions for in-vehicle networking and data transmission.
• FPD-Link (proprietary). Developed by Texas Instruments, this high-speed digital video interface is widely used in automotive applications. It supports high-resolution video and data, making it a strong competitor.

Link	Owner / body	Type	Main use
OpenGMSL	OpenGMSL Association (based on ADI GMSL)	Open, asymmetric SerDes	Cameras, sensors, displays
MIPI A-PHY	MIPI Alliance, IEEE 2977	Open, asymmetric SerDes	Cameras, sensors, displays
ASA Motion Link	Automotive SerDes Alliance	Open, asymmetric SerDes	Cameras, sensors, displays
FPD-Link	Texas Instruments	Proprietary SerDes	Cameras, displays
Automotive Ethernet	IEEE 802.3 (for example 802.3ch, 802.3cy)	Open, packet network	Backbone and zonal networking, some cameras
Chinese standards	Chinese industry alliances	Open, regional	Cameras, displays, networking

Promoters of OpenGMSL

OpenGMSL is backed by a group of industry leaders, including car makers, suppliers, semiconductor companies and test equipment vendors. The OpenGMSL Association manages the standard and promotes collaboration across the automotive ecosystem.

Key promoters include:

• Analog Devices, Inc. (ADI). The main developer of GMSL technology, ADI provides the foundation for OpenGMSL.
• Car OEMs and Tier-1 suppliers. Various vehicle makers and suppliers are taking part in the initiative to improve their connectivity solutions. Launch coverage in 2025 reported members such as Hyundai Mobis, Aptiv and Geely alongside chip and test companies including Qualcomm, GlobalFoundries and Keysight; check the association's site for the current list.

ADAS vision systems

Advanced driver assistance systems (ADAS) make driving safer and more convenient. They combine sensors, cameras and AI to help drivers avoid accidents and drive more easily. The main vision functions are:

• Pedestrian detection and avoidance. Cameras and sensors detect pedestrians and help the car avoid collisions.
• Lane departure warning and correction. Alerts the driver if the car starts to drift out of its lane and can steer it back.
• Traffic sign recognition. Cameras read traffic signs and show the information to the driver.
• Automatic emergency braking. Detects likely collisions and applies the brakes to prevent or reduce an accident.
• Blind spot detection. Monitors the car's blind spots and warns the driver of vehicles in them.

These systems rely on high-quality video arriving with low, predictable latency. That is where standards like OpenGMSL come in: reliable, high-speed transmission lets ADAS vision systems work as intended and makes roads safer. Because these are safety functions, the link also has to support diagnostics and error detection that fit an ISO 26262 safety case.

Display systems

Alongside ADAS, modern vehicles carry advanced displays that give drivers critical information and improve the experience. Display systems are evolving in four main areas:

• Instrument clusters. Digital clusters replace analog gauges with high-resolution screens showing everything from speed and fuel to navigation and ADAS alerts.
• Head-up displays (HUDs). HUDs project key information onto the windscreen, so drivers keep their eyes on the road while seeing speed, directions and warnings.
• Infotainment systems. Central displays give access to entertainment, navigation and vehicle settings, often with touchscreens, voice control and smartphone integration.
• Rear-seat entertainment. High-resolution rear screens offer films, games and internet access on long journeys.

All of these need high-speed, reliable data links, and OpenGMSL is designed to provide that connectivity.

In-vehicle networking and Ethernet

In-vehicle networking connects the many electronic units in a car so they communicate effectively. Automotive Ethernet is a key technology here, offering high-speed data transfer and robust performance:

• High bandwidth. Automotive Ethernet supports high data rates for ADAS, infotainment and autonomous driving, and can carry the large volumes of data produced by cameras, sensors and other devices.
• Low latency. Low, bounded latency (helped by time-sensitive networking features) supports real-time communication between components, which matters for safety and performance.
• Scalability. It scales across vehicle architectures, from basic models to high-end, feature-rich cars.
• Cost-effectiveness. Standardised Ethernet technology helps car makers reduce cost and simplify the integration of new features.

In practice SerDes links and Ethernet are complementary. SerDes links like OpenGMSL move raw sensor and display streams point to point with minimal latency, while Ethernet forms the backbone between zone controllers and central computers.

Common mistakes when choosing a link

• Sizing the link for today's camera rather than the sensor planned for the next platform.
• Ignoring the back channel and power-over-coax budget until late in the design.
• Assuming open means interoperable on day one; compliance testing and certified parts take time to arrive.
• Treating cable and connector loss as an afterthought: reach at high data rates depends heavily on the harness.

Industry impact

OpenGMSL is positioned to have a real impact on the automotive industry. By providing a standardised, high-performance solution for in-vehicle connectivity, it meets the growing demand for ADAS and autonomous driving. It can raise the performance and reliability of these systems and encourage innovation and collaboration across the industry.

As cars get smarter and more connected, standards like OpenGMSL will shape the future of vehicle connectivity. A robust, open and collaborative platform can drive progress in autonomous driving, ADAS and infotainment, making roads safer and driving more enjoyable. How it fares against A-PHY and ASA-ML will depend on how quickly second-source chips and compliance programmes appear.

FAQ

Is OpenGMSL the same as GMSL?

It is based on GMSL, but managed as an open standard by an association rather than as a single vendor's product line, so other companies can build compatible devices.

Does OpenGMSL replace automotive Ethernet?

No. It carries point-to-point camera and display streams, while Ethernet connects computers and zones across the vehicle.

How does OpenGMSL differ from MIPI A-PHY?

Both are open, asymmetric SerDes standards for the same job. OpenGMSL starts from a large installed GMSL base; A-PHY was written from the start as an industry standard by the MIPI Alliance.

Want to take part? The OpenGMSL Association's website explains how companies can join and contribute. Share your thoughts and experience with OpenGMSL in the comments below.