output of CCD to preamp

[Mike Hoffberg]

The output of the CCD usually resides at a DC offset from the ground.
(In particular, the Thomson TH7895 seems to have an offset of about 11
volts).  

The ADC used to digitize the output is expecting a signal with zero
offset.

The question I have is what is the best way to remove the offset:

AC coupling?
This might be the "safest" because it would eliminate the fear of
grounding the output of the CCD.  If so, where do you put the cutoff
frequency of this high pass filter?  Should a higher order filter be
used to make the cutoff frequency higher?

(Can a transformer be used to AC couple the signal?)

DC restoring circuit?
Used in conventional video circuits, but the commercially available
ICs, do not provide the capability to remove 11 volts of off set at
high bandwidths.

Biasing the ADC to 11 volts?
This would make the analog ground at 11 volts, the +Vcc @ 16V, the
-Vcc @ 6V.  This would allow the output of the CCD to be directly
coupled to a preamp (buffer) which would then go to the input of the
ADC.  The digital outputs of the ADC could be optically isolated from
the digitizer.  I am not sure as to how one goes about biasing the
AGND.  Is it attached to a potential that is at that bias level (from
the ground of the CCD and drivers?), making sure that the +Vcc and
-Vcc are from supplies that have floating grounds?

Once I am writing this message:
Has anyone come up with a high bandwidth serial link (100+ MB/s)?

Gazell HotRod - no longer in production (1 Gb/s)
AMD TAXI - no longer in production for high data rates (150 Mb/s)
Cypress HotLink - too slow (330 Mb/s)
IEEE1394/Fire Wire - way too slow, for now (100-200 Mb/s)
IBM SSA - only 20 MB/s??

FiberChannel - Fastest out there? (1 Gb/s)

MIKE

-- 
Michael Hoffberg                 /.\ Argonne   
hoffberg at aps.anl.gov            // \\ National 
mike at anl.gov                   //_O_\\ Lab     
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