audio/videoZONE Products for the week of October 4, 2004
Fairchild Semiconductor Says . . .
FSAV430: 800 MHz Video Switch Allows Design Flexibility
for High-Res Displays
Excellent OFF Isolation Prevents Ghosting In High-Resolution
Applications
Fairchild Semiconductor, one of the largest suppliers of analog switch solutions, announced the FSAV430, a high-performance Quad SPDT (2-to-1 multiplexer/demultiplexer) video switch. Its ultra-wide 800 MHz <3 db) bandwidth allows full design flexibility while maintaining absolute signal fidelity. The FSAV430's low-power (<1µA) operation reduces power consumption in LCD monitors and portables, and its excellent OFF isolation <75dB) eliminates annoying monitor ghosting effects. The switch's low differential gain and phase maintain stable color saturation and hue consistency over the full range of brightness levels. In slim DVD designs for video output connection sharing, the FSAV430 is ideal for emerging high-resolution video applications including HDTV and UXGA monitors.
"The FSAV430 device addresses designers' specific challenges in
high-resolution video applications," says Jerry Johnston, Fairchild
product manager for analog switches. "The combination of wide bandwidth,
excellent OFF isolation and low differential gain offers superb high-resolution
performance for portable designs and space-constrained applications requiring
small package size and low power consumption."
analogZONE Says...
There is very little to be said about this announcement apart from saying it's "about time" a vendor looked at a high frequency solution such as this.
The configuration is a typical bidirectional quad SPDT analog switch which can be configured as a 2:1 muliplxexer or demultiplexer. The control is TTL compatible while the quiescent power consumption is less than 1 µA.
The data sheet quotes the -3 dB bandwidth as 800 MHz working in 75-ohm systems with off-isolation at -75 dB and channel crosstalk also at -75 dB (both at 10 MHz). Space has been left on the data sheet for NTSC differential phase and gain characterization and one has to think "why bother?" when we are talking about wideband signal systems. I would rather know what was happening to phase and gain at various levels at 30 MHz rather than 3.58 MHz!
The on-resistance with a 1-V signal is a typical 5.0 ohm, falling to 4.5 ohm with a 2-V signal. Flatness of the on-resistance is a typical 1.0 across the input voltage span (which is up to the rail -- recommended between 3.0 V and 3.6 V). The worst turn-on time is 7 ns and the worst turn-off time is 4 ns. That turn-on time limits the part's applications in continually-switching systems to about 140 MHz, which is not an application that it was designed for -- but for which it may also well be employed.
Although specifically designed for the volume applications of component video switching (GBR or YPbPr) in products such as televisions, monitors and home theater receivers it will also be useful as a coaxial relay replacement for RF switching up to about 150 mW -- which covers a huge number of potential applications. This part will do exceptionally well.
The FSAV430 is sampling now with production during this month (October 2004) and available in Pb-free TSSOP-16, QSOP-16 and depopulated QFN-16. Pricing is $1.50 in 1000-piece lots.