Gage CompuScope 14100C, Hardware Manual And Driver Installation Manual

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100 CompuScope 82GC
CompuScope 82GC triggering
CompuScope 82GC features state-of-the-art triggering.
An analog comparator provides triggering from either one of the input channels, or from an external signal or
from software.
In addition to the trigger source, trigger level and slope are also selectable by software, making the trigger
system similar to traditional oscilloscopes.
The user can software-select the trigger source from any one of the following:
•
Channel 1
•
Channel 2
•
External Trigger
•
Software Trigger
The selected trigger source is then compared to a trigger level set by an on-board, 8 bit software-controlled
DAC. An on-board, high-speed comparator is used for this function, making it possible to trigger on narrow
pulses or glitches that are much shorter than the sample rate, subject to the 300 MHz bandwidth limitation of the
front-end trigger circuitry.
Each time the selected signal crosses the trigger level, the on-board triggering circuitry monitors it for the slope
selected by the user. When the appropriate slope is detected, a Trigger signal is generated.
Figure 62: Generation of a trigger signal – negative slope
External Trigger amplifier
The External Trigger input also has oscilloscope-like 1 M
Ω
/ 25 pF input impedance.
Gage’s proprietary input-protection circuitry allows the FET stage to withstand voltages as high as
±
15 Volts
without causing any damage to the inputs.
The trigger comparator has an operating range of
±
1 Volt.
Software-selectable attenuation of X1 or X5 on the External Trigger input allows input ranges of
±
1 Volt and
±
5
Volt, respectively.