SerDes provides real-time bidirectional control for driver-assist cameras

June 16, 2010 // Christoph Hammerschmidt

National Semiconductor unveiled its FPD-Link III family of automotive-grade serializer and deserializer (SerDes) chipsets featuring the industry's first real-time, bidirectional control channel for driver-assist video cameras. The FPD-Link III chipsets improve driver safety and response time by delivering clock, data, and real-time I2C bidirectional control, continuously over a single differential pair.

Camera systems have become an important automotive safety component, typically combining multiple camera modules with advanced image analysis to help drivers monitor road conditions, detect hazards and avoid collisions. Automotive safety system designers can now use National's FPD-Link III embedded clock SerDes to connect cameras and displays to an electronic control unit (ECU) with minimal software overhead and fewer wires, reducing cost and weight.

National's DS90UB901Q serializer and DS90UB902Q deserializer are designed for automotive camera systems with 14-bit color depth. The chipset employs cyclical redundancy check (CRC) to validate and monitor data integrity and eliminates the need for an additional control wire to the camera module. Unlike alternatives that relegate control data into the blanking periods or small gaps between video frames, National's proprietary back-channel technology delivers continuous, real-time communication between several remote camera heads and the ECU. Real-time communication provides the immediate control needed to synchronize multiple sideview and rearview cameras, enabling image stitching that delivers a 'birds-eye' view to assist drivers with blind spots, lane departure, collision avoidance and parking.

National's FPD-Link III family also includes the DS90UB903Q serializer and DS90UB904Q deserializer, which support the 18-bit color depth needed for in-vehicle infotainment systems. The SerDes chipset connects the graphics host processor with central information displays, rear seat entertainment displays and navigation displays. The SerDes’ integrated real-time control channel enables faster response times for touch screen displays and eliminates the need for external control cables and connectors.

Both chipsets serially route video content over distances in excess of 10 meters and support continuous pixel clock ranges from 10 MHz to 43 MHz and display resolutions up to SVGA. They are AEC-Q100 Grade-2 qualified for operation between -40 degrees C and 105 degrees C, and are powered by a 1.8V supply. They also feature a built-in self test (BIST) mode for factory test, system start up and diagnostics.

To protect adjacent circuitry from electromagnetic interference (EMI), the FPD-Link III chipsets generate a spread-spectrum clock to modulate the deserializer output to minimize harmonic peaking. The SerDes’ EMI performance ensures that infotainment and driver assist high-speed data links can meet rigorous automotive requirements.

Available now, the DS90UB901Q serializer (32-pin LLP) and DS90UB902Q deserializer (40-pin LLP) chips are priced at $5.61 each in 1,000-unit quantities. For more information, visit www.national.com/pf/DS/DS90UB901Q.html and www.national.com/pf/DS/DS90UB902Q.html.

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December 15, 2011 | Texas instruments | 222901974

Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.