PAS302BCW-22S

CMOS Image Sensor IC

Version 2.4, 20 Sep. 2005

PixArt Imaging Inc.

E-mail: fae_service@pixart.com.tw

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3. Function Description

3.1 Defect Compensation

The Defect Compensation block can detect the possible defect pixel and replace it with average

output of like-colored pixels from near side of defect pixel. There is no limitation capability of

defect pixel number. This function can be programmed to enable/disable by user.

3.2 Companding Curves

The companding function which means compressing and expanding is used to simulate the

gamma curve and do non-linear transformation before the data is output. There are 4 curves

selected by setting Register Compand_Sel as shown in Fig. 3.1. This function can be

programmed to enable/disable by user.

11,1111,1111

00,0xxx,xxxx 00,1xxx,xxxx

10,xxxx,xxxx

11,xxxx,xxxx

010

011

O/P ( 10-Bit)

I/P ( 10-Bit)

3

0

1

2

without companding

Figure 3.1 Companding curves programmed by Compand_EnH and Compand_Sel.

3.3 Power Down Mode

The PAS302BCW-22S can be powered down by setting register “Sw_PwrDn” = 1 or by enable

Pwdn pin. The register value will sustain in the power down mode. PAS302BCW-22S supports 2

power down modes:

Software power down：Set register “Sw_PwrDn” = 1 to power down all the internal block

IC

.

Hardware power down：Pull Pwdn pin to high to power down the chip. The chip will go into

standby mode.

3.4 Reset Mode

The PAS302BCW-22S can be reseted by setting register “Sw_Reset” = 1 or by enable Reset

pin. PAS302BCW-22S supports 2 reset modes:

IC

registers.

Hardware reset：Pull Reset pin to high to reset the full chip.