74
•
Technical Specifications
X64 Xcelera-HS PX8 User's Manual
Output Details:
•
Each output has ferrite beads plus a 680 ohm series resistor on the cathode (+) connection.
•
The diode and capacitor provide reverse voltage protection and noise filter
•
Maximum output device differential voltage is 25V.
•
Maximum output device sink current is 35mA with 25V output differential.
•
Maximum reverse voltage is 25V.
•
Maximum output switching frequency is limited by driver and register access on the PCIe bus.
Note 3: External Trigger Input Specifications
The two Trigger Inputs are opto-coupled and compatible to differential signals (RS-422) or single
ended source signals. The following figure is typical for each External Trigger Input.
3v3
FB
FB
External
650
110
13.3K
nTrig In
External
Trigger-
SW2
Figure 33: External Trigger Inputs Electrical Diagram
•
For single ended signals, the External Trigger - pin is connected to ground. The switch point is
~2V by default to support TTL 5V signals and can be changed to switch at ~10V with SW2 to
support 24V industry standard signals.
•
For RS-422 differential signals, switch point must be selected to ~2V.
•
Maximum external signal input voltage is 26V, irrelevant of the selected switch point.
•
The incoming trigger pulse is “debounced” to ensure that no voltage glitch is detected as a valid
trigger pulse. This debounce circuit time constant can be programmed from 1
µ
s to 255
µ
s. Any
pulse smaller than the programmed value is blocked and therefore not seen by the acquisition
circuitry. If no debouncing value is specified (value of 0
µ
s), the minimum value of 1
µ
s will be
used.
•
Each input has a ferrite bead plus a 650 ohm series resistor on the opto-coupler anode.
•
Maximum input signal frequency is 100 KHz.
•
Opto-coupler response time is 0.5
µ
s for a rising signal.
•
Opto-coupler response time is 4.2
µ
s for a falling signal.
•
Refer to Sapera parameters:
CORACQ_PRM_EXT_TRIGGER_SOURCE
CORACQ_PRM_EXT_TRIGGER_ENABLE
CORACQ_PRM_EXT_TRIGGER_LEVEL
CORACQ_PRM_EXT_FRAME_TRIGGER_LEVEL
CORACQ_PRM_EXT_TRIGGER_DETECTION
CORACQ_PRM_EXT_TRIGGER_DURATION
•
See also *.cvi file entries:
External Trigger Level, External Frame Trigger Level, External Trigger Enable, External Trigger
Detection.
•
External Trigger Input 2 used for two pulse external trigger with variable frame length line scan
acquisition.
