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CV-A33CL
 
 
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6. Functions and Operations 
In the following the format shown in “7.3. CV-A33CL command list” are used for function 
commands and parameters.  
6.1. Basic functions  
The CV-A33CL camera is a progressive scan camera with 10 or 8 bit video output in single 
channel Camera Link.  
Programmable partial scan, where the start line and the number of lines can be selected with 1 
line increment is also available. 
There are 4 modes: Normal continuous, and 3 trigger modes: Edge Pre-Select (EPS), Pulse Width 
Control (PWC) and Auto Trigger. 
The accumulation is LVAL a-synchronous. 
In the following some of the functions are shown in details. 
 
6.1.1. CMOS Sensor 
The CMOS sensor principle layout is shown.  
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2 x 10 bit digital shift register
Video
process
Pixel
Column
Process
and A/D
Control
and
set up
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2 x 10 bit digital shift register
Video
process
Pixel
Column
Process
and A/D
Control
and
set up
The sensor is an array of active photosensitive 
pixels. The global shutter is working 
simultaneously on all pixels. The readout can be 
random row by row. 4 columns are feed through 
a 4 to 1 multiplexer to an A/D converter. The 
digitized row signals are placed in a vertical 
register by a 1 to 4 multiplexing. From here it is 
read out with the pixel clock pulses, even if the 
window of interest has fewer columns. The 
frame speed depends only of the height of the 
window, not of the width.  
Pixel principle and column processing with A/D 
converting is shown below. 
 
 
Fig. 7. CMOS principle layout 
 
6.1.2. Pixel principle 
Each pixel consists of a sensing part, a pixel memory 
and an amplifier. The function can in short be 
described. The photo diode and charge capacitor is 
reset when switch 1 is closed. The signal accumulation 
starts when sw 1 open. The charge is transferred to the 
pixel memory capacitor when sw 2 close. The 
accumulation stop when sw 2 open, and the signal is 
now temporary stored in the memory capacitor. After 
reset of the charge capacitor, a new accumulation can 
start. The signal on the pixel memory capacitor is read 
out to the column by the read row signal. The memory 
can now be reset. 
Start exposure
Stop exposure
Reset
memory
Light
Photo
diode
Pixel
memory
Read row
To column 
processing
Buffer
amplifier
1
2
3
4
Charge
capacitor
Start exposure
Stop exposure
Reset
memory
Light
Photo
diode
Pixel
memory
Read row
To column 
processing
Buffer
amplifier
1
2
3
4
Charge
capacitor
        Fig. 8. Pixel principle. 
With this construction all pixels will integrate at the same time, (Global shutter). The resulting 
image is temporary stored in the pixel memory during read out, while a new exposure can be 
started.  
All timing is set up in the timing block by an internal serial link.