Visit the Avago Technologies web site
Click on the advert above to visit the company web site

Product category: Communications ICs (Wired)
News Release from: National Semiconductor | Subject: SCAN921025H and SCAN921226H
Edited by the Electronicstalk Editorial Team on 04 February 2005

Serdes chipset survives automotive
environments

Request your FREE weekly copy of the Electronicstalk email newsletter. News about Communications ICs (Wired) and more every issue. Click here for details.

The SCAN921025H serialiser and SCAN921226H deserialiser deliver up to 10bit digital data at 20 to 80MHz over a single point-to-point differential interconnect in backplanes or cable.

The SCAN921025H serialiser and SCAN921226H deserialiser deliver up to 10bit digital data at 20 to 80MHz over a single point-to-point differential interconnect in backplanes or cable The serdes (serialiser/deserialiser) chipset operates in harsh environments up to 125C

Harsh automotive and industrial environments require a serdes that can withstand high temperatures, and includes testability for continuous, reliable operation.

For example, video cameras mounted in automotive roof enclosures must operate reliably on hot summer days.

The transfer of high-speed industrial data in electrically noisy factories is another example.

To enable system testing in these environments, National has integrated BIST (built-in self-test) and JT into the SCAN921025H serialiser and SCAN921226H deserialiser.

"Features such as extended temperature and JT further expand our high-speed interface market presence in the industrial and automotive segments", said Jeff Waters, Product Line Director for the Communications Interface group at National.

"Automotive and industrial data transfer and display applications demand robust products, and National will continue to meet those needs through innovations in ruggedness and testability".

National's high-speed LVDS SCAN921025H serialiser transforms a 10bit wide parallel LVCMOS/LVTTL databus into a single high speed serial data stream with embedded clock.

The SCAN921226H receives the LVDS serial data stream and converts it back into a 10bit wide parallel databus plus clock.

This single serial-data path makes PCB design easier, and the reduced cable, PCB trace count, and connector size significantly reduces cost.

Another system cost saving feature comes from embedding the clock in the serial data stream.

This eliminates the clock-to-data and data-to-data skew problem.

On power-up of the serialiser, the engineer can choose to activate the synchronisation mode or allow the deserialiser to use the lock-to-random-data feature.

By using the synchronisation mode, the deserialiser will establish lock to a signal within specified lock times.

By utilising the lock-to-random-data feature, the receiver synchronises automatically to raw data without system intervention, training patterns, or the need for an accurate reference clock.

This feature is valuable in cable applications where there is no feedback from the receiver to transmitter boards.

The SCAN921025H serialiser and SCAN921226H deserialiser operate between 20 and 80MHz, delivering full data payloads from 200 to 800Mbit/s.

This serdes chipset is compliant with the IEEE1149.1 standard for boundary scan test.

IEEE1149.1 features provide the design or test engineer access via a standard test access port (TAP) to the backplane or cable interconnects and the ability to verify differential signal integrity.

The chipset also features an at-speed BIST (built-in self-test) mode which allows the data transmission path between the serialiser and deserialiser to be verified at speed.

National Semiconductor: contact details and other news
Email this article to a colleague
Register for the free Electronicstalk email newsletter
Electronicstalk Home Page

Search the Pro-Talk network of sites

Visit the Avago Technologies web site