VCSBC4012.pdf – VCSBC4012 Single Board Smart Camera Operating Manual
14
4.2.3 Electrical
specifications J2 camera socket
All Signals are Low Level TTL (3.3V), not opto isolated.
The electrical specifications given for the trigger input and output are also valid for the remaining
LVTTL IOs.
The following Signals have a 1k5 pull up
resistor on board:
-
I2C_Clock
-
I2C_Data
-
Trig_in
Trigger IO Specifications:
The board features a dedicated fast TTL trigger input (for use as image capture trigger) and a fast TTL
trigger output (as strobe-light trigger). Since both signals are fast at a very low noise margin, it is
recommended to keep the cable as short as possible. Use twisted pair or even coaxial cable for this
purpose. The trigger input assures a constant image capture delay without jitter.
Electrical Specification of trigger input
5
:
input voltage: Signal LOW
-0.3V – 0.8V (LVTTL)
Input voltage: Signal HIGH
2V – 3.9V (LVTTL)
input current:
N/A
limiting resistor:
1K5 pull up
reverse voltage protection:
none
switching delay:
none
Image trigger on rising or falling input signal works as before – see section 6.5.1 for details.
The trigger input and output are very sensitive and not galvanically separated. Opto
isolation of the driving circuit is therefore strongly recommended. The following page
shows suitable circuits for trigger input and output.
!
Please note that input and output are not protected against over current. The output is neither
protected against short circuit nor reverse voltage spikes from inductive loads.
Use the VC4018 or VC4016 cameras if you can not provide a suitable trigger input driving
circuit. These cameras include the same hardware as the VCSBC4018 / -16, but opto isolation
of the trigger input and output is already included.
5
The electrical specifications given for the trigger input and output are also valid for the
remainingLVTTL IOs.
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1996-2011 Vision Components GmbH Ettlingen, Germany
