Could this be a problem? I'm not sure what speeds everything is happening at. Is it possible that clocks are getting sent too fast for the sensor, or faster than the pixel can be read into the array?Although the linear array is capable of running over a wide range of operating frequencies up to a maximum
of 5 MHz, the speed of the A/D converter used in the application is likely to be the limiter for the maximum clock
frequency. The voltage output is available for the whole period of the clock, so the setup and hold times required
for the analog-to-digital conversion must be less than the clock period.
Edit-
It seems that digital read/writes take about 3.5us for 10.5us per pixel which is about 100khz, so that is way under the 5Mhz max. With ShiftIn I presume Clk=Low won't happen until the digitalRead is done.
My other question is how is 2v-3v out of the sensor going to be interpreted by the digital input, especially with the pulldown resistor in there? The fact that I am using 270ohm instead of 320 couldn't be critical, could it?