Ana lo g Line Sc a n Ca m e ra
Input Signals
Table 2. Video Offset Switch Settings
The LC3000 camera requires a single DC
supply (+12 to 24VDC) for operation. An
internal oscillator sets the default data
output rate to default model rate (10 or
20 MHz), and the camera will operate at
the maximum line rate. The camera can
be further controlled by three externally
generated differential input signals:
Master Clock (MCLK), Line Transfer
(LT), and Line Reset (LR).
Range DIP Switch #6 DIP Switch #7 DIP Switch #8 Normal Offset (mV)
0
1
2
3
4
ON
ON
ON
ON
OFF
ON
ON
ON
OFF
ON
0
6.4
OFF
OFF
ON
12.8
19.3
25.7
OFF
ON
5
6
OFF
OFF
ON
OFF
ON
32.1
38.6
OFF
7
OFF
OFF
OFF
45.0
The Master Clock input determines the
data rate frequency for values up to
maximum clock of the camera. The
MCLK input is optional, as the camera
is preset to run off of the internal oscil-
lator at the default maximum data rate.
Should a data rate slower than that
default rate be necessary, an externally
supplied master clock can be enabled
by selecting that setting through the
bank of DIP-switches. The data rate
may be run from 20 kHz to cameras
maximum clock rate. External line
transfer operation also can be enabled
on the DIP-switch bank.
Table 3. Video Gain Switch Settings
Gain Times
Full Scale
Range DIP Switch #3
DIP Switch #4 DIP Switch #5
0
1
2
3
4
ON
ON
ON
ON
OFF
ON
ON
ON
OFF
ON
0.67
1.00
1.50
2.20
3.35
OFF
OFF
ON
OFF
ON
5
6
OFF
OFF
ON
OFF
ON
5.00
7.50
OFF
7
OFF
OFF
OFF
11.20
The Line Transfer input signal transfers
the charge from each photo site to the
readout registers. The readout registers,
in turn, transport the charge from each
photodiode in succession to the video
outputs. The LT input from the user
must remain in the ON state for at least
two MCLK cycles to initiate the inter-
nal line transfer and may remain ON
until 2 clock cycles prior to the next
desired line transfer. Because there are
extra stages in the CCD sensors readout
register, a minimum number of MCLK
cycles (the number of elements on the
CCD sensor plus 41) must exist
camera can be separately controlled
by using the external line reset input.
The LR input is active low (ON) in
polarity and therefore, when not in
use, must be held high (OFF). In this
condition, the exposure time is
defined by the period of the LT signal.
When using the LR input signal, the
exposure period is defined to be the
time between the rising edge of LR to
the rising edge of LT. The LR signal
must be held active low (ON) for a
minimum of 4 clock cycles and must
be inactive high (OFF) for a minimum
of 4 clock cycles prior to the
of the CCLK signal can be used to cap-
ture analog video data by a frame grab-
ber or digitizer.
The Line Enable (LEN) signal brackets
the valid analog video. The signal
becomes high one CCLK period before
the first valid pixel and goes low one
CCLK period before the last valid
pixel. The video output is a contiguous
pixel data stream with a dynamic
range (defined as peak video divided by
rms. pixel noise) of greater than 500:1.
between successive LT commands.
The Camera Line Transfer (CLT) out-
put signal is an internally generated
sync signal. Its falling edge indicates
the start of a line readout sequence.
This signal may be used for control-
ling strobes, shutters or other acces-
sories of the users system.
The maximum line scan period with-
out exposure control is 20 millisec-
onds. Integration times longer than 20
ms can introduce higher levels of dark
current, which reduces the dynamic
range of the sensor. Longer integration
times are possible, however, if the cam-
era is cooled, which reduces dark cur-
rent. Specific application characteris-
tics, such as light level and rate of
object motion, will determine the
LT signal.
Output Signals
The LC3000-series camera provides
three output synchronization signals:
Camera Clock (CCLK), Line Enable
(LEN), and Camera Line Transfer (CLT).
The Camera Clock (CCLK) operates at
either the MCLK frequency or default
camera frequency, and is synchro-
nized to the analog video. The output
optimum setting. Exposure time of the
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