ATM CCD cookbook trouble

["Antonio de Ugarte Postigo" <ugarte@mad.servicom.es>]

Hello everybody,

We are building a CCD  cookbook camera. Everything was going fine until we
got to the final test 
of the interface card. We installed the analog-to-digital converter (ADC)
we built the test circuit, installed
it and we began the tests. The three first steps ask you to check the
voltages at three of the pins of the 
ADC, the results were perfect. We were then asked to turn the potenciometer
and check how the voltage
output at the JS sig. it should have varied from 0 to 4.2V but it went up
to 5.10V ( the output signal of the +5V).
As the test program says there should be a drop of voltage between this two
points because of the 1kOhm 
resistor. We would like to know if anyone has any idea of what could this
be due to.... please.... I'm desperate... :-(

        Everything seems to be ok so The problem might be in the ADC chip
(AD1674JN). But we would like to be 
sure before changing it. It is not easy to find it here in Spain, so we
would apreciate if someone would tell us where 
we could find one in the web. We got ours from the kit sold by University
Optics

Please help, we really don't know now what to do :-(
Thanks a lot

Maria Angeles Agudo Garcia
Antonio de Ugarte Postigo