Philips Semiconductors
Product specification
Frame Transfer CCD Image Sensor
FT 18
Architecture of the FT 18
The FT18 consists of a shielded storage section and an open image
section. Both sections have the same structure with identical cells
and properties. The only difference between the two sections is the
optical light shield.
The storage section is controlled by four storage clocks (B1 to B4).
An output register is located below the storage section for read-out.
The output register has buffers at both ends.This allows either normal
or mirrored read-out.
The optical centres of all pixels in the image section form a square
grid. The charge is generated and integrated in this section. The
image section is controlled by four image clocks (A1 to A4). After
integration, the image charge is completely shifted to the storage
section. The integration time is electronically controlled by charge
reset (CR).
Transport of the pixels in the output register is controlled by three
register clock phases (C1 to C3).The register can be used for vertical
binning. Horizontal binning can be achieved by summing pixel
charges under the floating diffusion. More information can be found
in the application note.Figure 2 shows the detailed internal structure.
IMAGE SECTION
10.9 mm
1:1
Image diagonal
Aspect ratio
Active image width x height
Total width x height
7.680 x 7.680 mm2
8.040 x 7.860 mm2
7.5 x 7.5 µm2
100%
Pixel width x height
Geometric fill factor
Image clock pins
A1, A2, A3, A4
<3.75nF per pin
1024
Capacity of each clock phase
Number of active lines
Number of contour lines
Number of black lines
4 (top) + 1 (bottom)
8 (top) + 11 (bottom)
1048
Total number of lines
Number of active pixels per line
Number of overscan (timing) pixels per line
Number of black reference pixels per line
Total number of pixels per line
1024
8 (2x4)
40 (2x20)
1072
STORAGE SECTION
Storage width x height
8.040 x 7.860 mm2
Cell width x height
7.5 x 7.5 µm2
B1, B2, B3, B4
<4.1nF per pin
1072 x 1048
Storage clock phases
Capacity of each B phase
Number of cells per line x number of lines
OUTPUT REGISTER
Output buffers (three-stage source follower)
Number of registers
2
1 (bidirectional below storage)
Number of register cells below storage
Number of extra cells to output
1072
2 x 7
Output register horizontal transport clock pins
Capacity of each C-clock phase
Overlap capacity between neighbouring C-clocks
Reset Gate clock phases
3 (C1..C3)
<85pF per pin
<35pF
2 pins (RGL, RGR)
<15pF
Capacity of each RG
2000 January
3