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N

N+1

N−9

OB Calibration Cycle

DIN

(CCD IN)

SHP

SHD

CLPOB

BLKG

CLPDM

ADCCLK

D0–D11

N−8

N−7

Optical Black

Pixels

Dummy

Pixels

Active Image

Pixels

12 Clocks

12 Clocks

VSP1221

SLES012A – SEPTEMBER 2001 – REVISED JULY 2004

APPLICATION INFORMATION (continued)

A.

OB Calibration latency is 12 clocks. So, OB update starts 12 clocks after CLPOB is pulled low and stops 12 clocks

after CLPOB is pulled high.

B.

If active image pixels are located immediately after CLPOB goes high, the OB update will affect the adjacent 12

pixels.

C.

The device clocks are stopped during BLKG and CLPDM. Therefore, if these signals appear immediately after

CLPOB goes high, the OB calibration update for the subsequent 12 clocks will stop. So, its recommended to delay

BLKG and CLPDM by at least 12 pixels after CLPOB goes high.

Figure 10. System Timing Diagram Example

21