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Well Depth Considerations

 

The detector node capacitance for the CRC463 array is tex2html_wrap_inline6194 0.06 pF. The well depth  is then proportional to the actual reverse bias voltage across the detector; q = C V. Consequently, a detector reverse bias of tex2html_wrap_inline6194 160 mV is required for a well depth of 60,000 e. Our array has an odd-even column effect which causes the applied detector reverse bias on even columns to be lower than that on odd columns. This means that even columns have well depths tex2html_wrap_inline6194 80% smaller than odd columns.

Raw linearity curves for readout methods 2 and 3 are plotted in Figure 29 for an applied reverse bias of 600 mV. These show that saturation becomes severe at signal levels tex2html_wrap_inline6291 6500 ADU, corresponding to a well depth of 58500 e tex2html_wrap_inline6353 .

   figure498
Figure 29: Raw linearity curves for readout method 2 (left) and readout method 3 (right). The signal levels for the four output amplifiers are plotted separately. Saturation occurs at a well depth of tex2html_wrap_inline6194 6500 ADU.



Kabal
Thu Jun 5 16:44:21 EST 1997