New Video Decoder for Automotive Backup Safety Cameras
Last year the National Highway Traffic Safety Administration (NHTSA) mandated “rear-view visibility systems” on all cars, SUVs, light trucks and vans built as of May 1, 2018. The rear-view systems must show a 10 x 20-foot patch behind the car. The regulation was put into place as part of an effort to reduce motor vehicle backup fatalities. The non-profit organization kidsandcars says that between 1990 and 2013 1,189 child fatalities were caused by backups. NHTSA itself estimates that by 2054 when all vehicles have backup systems, 58–69 lives would be saved annually.
As automotive suppliers prepare to develop and install backup camera systems they face some technical challenges. For example, most systems do not respond well adapting to rapidly changing lighting conditions. To address this problem Intersil has introduced its new TW9992 analog video decoder for NTSC and PAL.
According to the company, the decoder’s Automatic Contrast Adjustment (ACA) image enhancement is able to automatically boost up or reduce the brightness/contrast of an image for greater visibility and safety. In addition, vehicle backup cameras typically employ differential twisted pair cables that require designers to use an op amp in front of the video decoder to convert the differential signal to single-ended. The TW9992 decoder eliminates the need for an external op amp by supporting direct differential CVBS (composite video baseband) signal inputs, thus reducing system cost and board space. The built-in short-to-battery and short-to-ground detection capability on each differential input channel is said to further enhance video performance and automotive system reliability.
TW9992 also features an integrated MIPI-CSI2 output interface that will provide compatibility with next generation SoC processors. MIPI is an international organization that develops interface specifications such as its Camera Serial Interface (CSI). MIPI CSI-2 has already achieved widespread adoption in the smartphone industry for its ease-of-use and ability to support a broad range of imaging solutions. The Intersil decoder’s MIPI-CSI-2 interface simplifies design by making it easier to interface with SoCs, while also lowering the system’s EMI profile. The TW9992 decoder takes both single-ended and differential composite video inputs from a vehicle’s backup safety camera.
The automotive-grade TW9992 analog video decoder is available in a 32-pin QFN package, and is priced at $3 USD in 1k quantities.