LTC3303

• Edge compute platform for machine vision and real-time sensor fusion for autonomous robots and vehicles applications
• 8 x GMSL2 camera interfaces with up to 6 Gbps/channel
• 10 Gbps SFP+ Ethernet interface
• IEEE 1588 Precision Time Protocol for synchronization with host systems and other edge devices
• Advanced embedded processing capabilities
• ROS2 compliant
• Advanced camera triggering functions and control features
• Open-source software stack and FPGA design to enable custom applications development

The AD-GMSL2ETH-SL is an edge compute platform enabling low-latency data transfer from eight Gigabit Multimedia Serial Link™ (GMSL) interfaces on to a 10 Gb Ethernet link. The target applications include autonomous robots and vehicles where machine vision and real-time sensor fusion is critical.

The system includes two MAX96724 Quad Tunneling GMSL2/1 to CSI-2 Deserializers, enabling connectivity to eight GMSL cameras. The video data from the cameras is transferred from the MAX96724 deserializers via MIPI CSI2 interfaces to an AMD KV26 System on Module which implements the logic to aggregate the video data from all the GMSL cameras into a 10 Gb Ethernet link, so that it can be sent to a central processing unit.

The IEEE 1588 Precision Time Protocol (PTP) with hardware timestamping is supported, enabling accurate synchronization with host systems and other edge devices. The AD9545 Quad Input, 10-Output, Dual DPLL/IEEE 1588, 1 pps Synchronizer and Jitter Cleaner is used to generate the required clocks for the 10 Gb Ethernet interface and the PTP logic.

A software networking stack can be used to realize the communication over the 10 Gb Ethernet link. Since the system runs Linux tools like gstreamer can be used to send the video data to a host and remote connection into the system is possible via ssh. The software network stack has limitations in terms of the maximum achievable transfer rate, and for this reason there is also the option to have an FPGA accelerated UDP or TCP implementation with Real Time Transfer (RTP) protocol for data packetization, which can get up to the maximum achievable data rate on the 10 Gb ethernet interface.

Accurate camera triggering control is achieved through dedicated FPGA logic, with configurable frequency and phase as well as selecting the trigger source between the internal logic and external signals.

Sixteen (16) general purpose I/O pins are available with software configurable functionality, operating at 3.3 V voltage level. A RS232 dedicated interface can be used to connect UART peripherals such as GNSS devices.

The design is accompanied by an open-source software stack and FPGA design, and reference applications, enabling custom software development to start from a proven implementation.

APPLICATIONS

• Autonomous robots and vehicles

• LTC3303A evaluation board
• Transient circuit included for load-transient evaluation
• EMI filter included to reduce noise in EMI emission tests

Demonstration Circuit DC3252A features the LTC3303A, 5 V, 4 A synchronous step-down silent switcher operating as a 2 MHz, 3.3 V to 1.2 V, 4 A buck regulator. The LTC3303A supports adjustable output voltages from 0.5 V to V_IN. The LTC3303A is a compact, high efficiency, and high-speed synchronous monolithic step-down switching regulator. A minimum on-time of 27 ns enables high V_IN to low V_OUT conversion.

The DC3252A operating mode can be selected as Burst Mode operation, skip (PS) or forced continuous (FC) mode. Setting JP1 to the SKIP position allows the LTC3303A to sync to a clock frequency from 1.6 MHz to 2.4 MHz. The LTC3303A operates in forced continuous mode when syncing to an external clock. The DC3252A also has an EMI filter to reduce conducted EMI. This EMI filter can be included by applying the input voltage at the VIN EMI terminal. The EMI performance of the board is shown in the EMI Test Results section. The red lines in the EMI performance graphs show the CISPR25 Class 5 peak limits for the conducted and radiated emission tests.

The LTC3303A data sheet gives a complete description of the device, operation, and application information. Full specifications on the LTC3303A are available in the LTC3303A data sheet available from Analog Devices, Inc., and must be consulted with the user guide when using the DC3252A evaluation board. The LTC3303A is assembled in a 2 mm × 2 mm FCQFN package with side wettable flanks (SWF) for visual solder inspection. The layout recommendations for low EMI operation and maximum thermal performance are available in the data sheet section Low EMI PCB Layout.

• GMSL2 prototyping system supporting the NVIDIA Jetson™ SoCs
• On-board MAX96724 that allows 4x GMSL2/1 camera inputs that allows for camera module bring-up, debug, and video streaming
• On-board MAX96717 that can be used for camera emulation and head-unit debug
• Enables development of GMSL applications with NVIDIA Jetson™ SoC
• SAMTEC connector that allows connection of any GMSL DPHY EV Kit to the NVIDIA Jetson™
• Additional inputs: USB, Ethernet, PCIe, and microSD card

The AD-GMSL522-SL is a GMSL-enabled NVIDIA Jetson Xavier™ NX-based carrier board and software solution that allows for simple camera to display conversion. This solution creates a scalable, user friendly, GMSL platform for receiving and transmitting data over a gigabit multimedia serial link (GMSL). The platform enables demonstrations and ecosystem development by serving as a hardware platform for software development.

The AD-GMSL522-SL supports two forms of camera input -- either straight CSI data coming through a SAMTEC connector, or via camera modules using GMSL2 or GMSL1 technology to connect to the on-board MAX96724 via COAX connectors. GMSL evaluation kits or any camera utilizing the standard 15- or 22-pin Raspberry Pi connector can be connected here using the AD-GMSLCAMRPI-SL adapter board.

The AD-GMSL522-SL package includes software tools to enable customers in their development of GMSL applications. Among these tools are modified L4T kernels that support certain camera modules and documentation that allows any user to update these kernels for their specific hardware needs.

The design incorporates the MAX96724GTN/VY+ Quad tunneling GMSL2/1 to CSI-2 deserializer and MAX96717GTJ/VY+ CSI-2 to GMSL2 serializer and provides a reliable platform to evaluate high-bandwidth GMSL.

There are two system options available for purchase: the AD-GMSL522-SL which is the base carrier board and does not include the NVIDIA SoM, and the AD-GMSL522-SOM-SL which is the carrier board including the NVIDIA Jetson Xavier™ NX SoM.

APPLICATIONS

• ADAS Camera Solutions
• Sensor Fusion ECU
• Driver and Occupant Monitoring
• In-cabin Infotainment