8

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LM9812 can correct for using its internal PGA.

Note 13:

Reference voltages below 1.80V may decrease SNR. Reference voltages above 2.20V may cause linearity (headroom) errors inside the LM9812. The

LM4041DIM3-ADJ (SOT-23 package) or the LM4041DIZ-ADJ (TO-92 package) bandgap voltage references are recommended for this application.

Note 14:

PGA Gain Error is the maximum difference between the measured gain for any PGA code and the ideal gain calculated by using the formula

where

.

CCD Output Signal

Gain

PGA

V

V

----





G

0

X

PGA code

32

---------------------------

+

=X

G

31

G

0

–

()

32

31

------

=