17 Feb
2009
17 Feb
'09
4:44 a.m.
On Tue, Feb 17, 2009 at 08:13:02AM +0100, Arnold Krille wrote:
But not only do they sync up to four AD-converters to
get one channel with
4GS/s (current state of the art is 8GS/s!), they also sync several of these
devices to act as one digital oscilloscope with multiple channels. They do the
syncing by 10MHz clock and somehow manage to distribute the trigger event to
all devices involved. Quite spooky and lot of hf to deal with.
Yep, 10 MHz is the standard for reference frequency
distribution for lab instruments. Getting decent GHz
clocks from that requires careful PLL design.
Returning to the original matter: multiplexing AD/DA
do exist of course, and they are the best solution
if you require lots of low bandwidth channels.
One reason you won't find many of them in pro audio
is the channel isolation requirement (> 100 dB)
- it would be very hard to make a fast analog
multiplexer reaching anything near that figure.
Ciao,
--
FA
Laboratorio di Acustica ed Elettroacustica
Parma, Italia
O tu, che porte, correndo si ?
E guerra e morte !