Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > Controls/MCUs

Video crosspoint switch promises black-level accuracy

Posted: 20 Sep 2006 ?? ?Print Version ?Bookmark and Share

Keywords:Intersil? ISL59534? video crosspoint switch?

Intersil's ISL59534 video crosspoint switch

Intersil Corp. has introduced a new 32x16 video crosspoint switch. The ISL59534 integrates a DC-restore clamp on each video input to eliminate black-level fluctuation, providing correctly balanced composite video with fewer external components, the company said.

The DC-restore clamp biases composite (NTSC and PAL) video by automatically adjusting the DC level of the most negative portion of the video to the reference voltage. This feature can be disabled by the user through an SPI/QSPITM compatible, three-wire serial interface for S-video and component video applications.

"Intersil's ISL59534 crosspoint switch provides black-level accuracy in composite video," said Kathryn Tucker, marketing manager for Intersil's video products group. "Proper video levels yield better picture quality and our integrated DC-restore function on the chip reduces fluctuation while eliminating pictures that are too light or too dark. The ISL59534 also eliminates the need for diodes, resistors and capacitors on each video input, resulting in cost and board space savings."

Clearer pictures, greater flexibility
The ISL59534 is suitable for routing video signals in security and video-on-demand systems. This device operates from a single +5V supply. It can accommodate voltages from 0 to 3.5V at the inputs and 0 to 4V at the outputs. It also has an input clamp with external group reference that can be used for AC-coupled applications.

Any of the device's outputs can be switched to any of the 32 input video signal sources. The device also features a broadcast mode in which any single input can be simultaneously sent to all 16 outputs. With 90MHz of bandwidth in broadcast mode, the device is suited for security applications. Outputs can be individually programmed to high impedance and a gain of +1 or +2 for greater flexibility.

The ISL59534 features a -3dB signal bandwidth of 320MHz. The device has a differential gain and differential phase of 0.025 percent and 0.022 and 0.1dB flatness out to 50MHz. This performance supports increasingly higher video resolutions and provides superior isolation for less leakage between video channels. The device also has a large output current for driving multiple video loads. Each output of the crosspoint switch can be put into a high impedance state so that several outputs can be connected together enabling much larger video matrices without adding rows of buffers.

Fast OSD switch
The new device offers an integrated fast on-screen display (OSD) switch in each output to enable users to switch in other graphicssuch as the location of the camera providing the video feedinto the video signal. OSD information can be inserted into any output through an internal, dedicated, fast 2:1 mux (15ns switching times) located before the output buffer. Intersil's OSD switch performs at speeds necessary for "glitchless OSD," or video signal switching without any noticeable smudging. The integration of OSD switch further reduces the BOM when compared to other competitive solutions.

The ISL59534 is part of Intersil's new line of video crosspoint switches that are footprint compatible with the company's single-chip 32x32 video crosspoint. Customers can use the same board design for a variety of different applications and choose the crosspoint that best fits their input and output requirements. This gives customers additional flexibility and reduces the need for unique board designs for different applications, Intersil said.

The ISL59534 is available today in a 356-lead BGA package and is priced at $65 in 1,000-unit quantities.

Article Comments - Video crosspoint switch promises bla...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top