Intersil, a subsidiary of Renesas announced the TW8844 LCD video processor that interfaces with the latest generation of automotive SoCs. The highly integrated TW8844 is said to be the first FullHD LCD video processor with analogue video decoder, two scalers and MIPI-CSI2 SoC interface.
The TW8844 is intended to provide the reliability automakers require to ensure their rearview camera systems are compliant with the U.S. Federal Motor Vehicle Safety Standard (FMVSS-111) for preventing injury or death caused by backover accidents and enables the migration from analogue to digital camera systems. It supports a variety of video interfaces and LCD panel resolutions up to full HD 1920 x 1080. The TW8844 LCD video processor is intended for centre stack/head units, full display rearview mirrors, instrument cluster displays and dual headrest rear-seat entertainment systems.
Automakers are starting to make rearview camera systems standard equipment for all new car models worldwide. In the U.S., the National Highway Traffic Safety Administration mandated in March 2014 that automakers implement “rear visibility technology” as standard equipment for all vehicles under 10,000 pounds, as part of the Kids Transportation Safety Act. The new FMVSS-111 regulation specifies that the area behind a vehicle must be visible to the driver when the vehicle is placed into reverse, thereby minimising blind spots. The law aims to reduce the number of deaths and injuries caused by driver backup accidents, many involving young children. The FMVSS-111 law requires that all new vehicles sold in the U.S., beginning in May 2018, have rearview backup cameras and the rear camera video must display in less than two seconds after the driver places the vehicle into reverse gear. (see the video below for more)
The TW8844 video processor with MIPI-CSI2 output and TW8845 video processor with BT.656 output exceeds the requirements of the FMVSS-111 law, displaying live video with graphics overlay in less than 0.5 seconds after vehicle ignition. The TW884x provides a robust rear-camera architecture to overcome the fast boot reliability issues inherent with today’s more complex center-stack systems. Today’s head units are prone to operating system (OS) software freezes and hang-ups that display a frozen image or prevent the rear camera from displaying live video. With SoCs running increasingly complex operating systems, software freezes and hang-ups are more common. The TW884x eliminates this problem by monitoring the SoC and camera output to determine if they are in a frozen or corrupted state. If the TW884x detects any issue, it bypasses the SoC and instantly displays the rearview camera video.
“The TW884x’s frozen detection feature is hardwired to trigger an interrupt signal if thresholds are violated, ensuring the vehicle’s rearview camera is FMVSS-111 compliant and live video is instantly displayed,” said Philip Chesley, senior VP of Precision Products at Intersil. “In addition, the TW884x’s rearview camera bypass architecture decouples the camera-to-display signal path from the rest of the infotainment system, which makes attaining an ISO 26262 functional safety rating on the camera system easier for automakers.”
Key Features and Specifications of TW8844 and TW8845 video processors
- Support several video inputs from analog or digital HD cameras:
- 10-bit ADC NTSC/PAL analogue video decoder supports differential, pseudo differential, and single ended composite video inputs (two differential or four single-ended), with built-in short-to-battery and short-to-ground diagnostics
- Two independent digital RGB input ports up to 24-bit RGB at 160MHz (1080p) each
- Two LVDS OpenLDI input ports (shares pins with the 2nd DRGB input) in 1-ch or 2-ch input mode, with 100MHz (max) per channel in 1-ch mode or 160MHz in 2-ch mode
- Support either one full HD input (1080p) or two HD inputs (720p)
- Provide system flexibility to drive most LCD panels:
- LCD path for TTL/TCON up to 24-bit DRGB, 160MHz (max)
- LVDS OpenLDI: dual channel, 100MHz (max) per channel in 1-ch mode or 160MHz in 2-ch mode
- TW8844 supports 4-lane MIPI-CSI2 output for up to 1080p, with up to 1Gb/lane
- TW8845 supports BT.656 output to the SoC with resolutions up to 720p
- Two input measurement engines with frozen/abnormal image detection diagnostics to monitor input from the SoC and camera
- EEPROM fast boot allows register programming without need for external microcontroller
- Two separate H/V scalers for outputting up to 1080p (1920 x 1080) resolution, allow processing of two different sources simultaneously, while outputting different data to the SoC and display, or they can simultaneously drive two different displays with different content
- Automatic Contrast Adjustment (ACA), white balance and gamma correction optimizes video quality (Shown in the video below
- Smooth input switching allows switching between various input sources without screen flicker
- AEC-Q100 Grade-2 qualified for operation from -40°C to +105°C
The TW8844 and TW8845 can be combined with Renesas’ R-Car SoC family, as well as the ISL78302 dual LDO, ISL78322dual 2A/1.7A synchronous buck regulator, and ISL78228 dual 800mA synchronous buck regulator to provide power rails for the TW884x, SoC and other key components on the automotive infotainment system board.
Pricing and Availability
The TW8844 video processor with MIPI-CSI2 output is available now in a 14mm x 20mm, 156-lead LQFP package, and is priced at $10.00 USD in 1k quantities. For more information on the TW8844 and evaluation board, please visit: www.intersil.com/products/tw8844.
The TW8845 video processor with BT.656 output is available now in a 14mm x 20mm, 156-lead LQFP package, and is priced at $9.50 USD in 1k quantities. For more information on the TW8845 and evaluation board, please visit: www.intersil.com/products/tw8845.