Preliminary, The analog plus compa, Xrd9827 c i s – Canon XRD9827REF User Manual

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... the analog plus compa

EXAR Corporation 48720 Kato Road, Fremont, CA 94538 Phone (510)-668-7000, Fax (510)-668-7030

PRELIMINARY

VRT

VRB

VDD

XRD9827

PIN 19

(RED)

2.2uF

PIN 16

(VDCEXT)

BANDGAP

1.24V

U
X

12K

Figure 7. Simplified Block Diagram Showing Global Offset Adjustment by XRD9827 Using

Internal Bandgap and CIS Using VDCEXT for Biasing

18. Set the dip switches to [001 01010000] to select the internal offset DAC for fine offset adjustment.
Push the Serial Port button. From the CAPTURE menu select SNAP SHOT. The offset should now move
the output of the CIS to almost zero scale. The other way to do a SNAP SHOT is by pressing CTRL and B
button at the same time. Please refer to data sheet for offset adjustment. A typical result of the fine offset
adjustment is shown below.