KAF−0402

www.onsemi.com

3

DEVICE DESCRIPTION

Architecture

Figure 2. Block Diagram

768 Active Pixels/Line

fR

SUB

4 Dark

10 Inactive

12 Dark

2 Inactive

4 Dark Lines

fV1

fV2

GUARD

fH1

fH2

KAF−0402

Usable Active Image Area

768 (H)

× 512 (V)

9

× 9 mm Pixels

3:2 Aspect Ratio

4 Dark Lines

The sensor consists of 784 parallel (vertical) CCD shift

registers each 520 elements long. These registers act as both

the photosensitive elements and as the transport circuits that

allow the image to be sequentially read out of the sensor.

The parallel (vertical) CCD registers transfer the image one

line at a time into a single 796-element (horizontal) CCD

shift register. The horizontal register transfers the charge to

a single output amplifier. The output amplifier is a two-stage

source follower that converts the photo-generated charge to

a voltage for each pixel.

Microlenses

Microlenses are formed along each row. They are

effectively half of a cylinder centered on the transparent

gates, extending continuously in the row direction. They act

to direct the photons away from the polysilicon gate and

through the transparent gate. This increases the response,

especially at the shorter wavelengths (< 600 nm).

Figure 3. Microlens

Silicon

Microlens

V1

V2