Acqiris SA230E User Manual page 64

5.2 Trigger modes and time-stamps
Self Trigger
In self-trigger mode an autonomous trigger signal is generated internally in the ADC module and output
through the front panel TRG OUT connector. This trigger signal consists of programmable periodic
pulses that are synchronous to the sample clock.
The self-trigger mode serves two purposes:
– Reducing system jitter by synchronizing the input signal to the sample clock
– Minimizing the impact of the synchronous noise of the ADC Card.
To use the Self-Trigger mode, the Trigger ActiveSource must be set to SelfTrigger.
Trigger signal synthesized (PIO3): The period has to be a multiple of 8 ns or it will be rounded to the
next 8 ns step. Please contact Acqiris for any specific demand relative to this limitation or to self
trigger.
Parameters
ActiveSource (IAqMD3Trigger.ActiveSource property): Specifies the trigger source.
There are three trigger sources: internal, external and self-trigger. If the Self-Trigger mode is selected
the Self-Trigger parameters should be set and the IO 3 output should be enabled.
Frequency (IAqMD3TriggerSourceSelfTriggerSquareWave Interface): Specifies the
frequency of the Self-Trigger square wave signal. The units are Hertz and range is [0.1, 125e6] .
DutyCycle (IAqMD3TriggerSourceSelfTriggerSquareWave Interface): Configures
the duty cycle of the Self-Trigger square wave signal. Units are percentage of the period. Range is
[0.1, 99.9].
Slope (IAqMD3TriggerSourceSelfTriggerSquareWave Interface): Specifies whether
a rising or a falling edge of the generated waveform triggers the acquisition module.
Out-AveragerAwg (ControlIOs interface): Self-Trigger signal is propagated through the IO
3.
64 Acqiris SA230E User's Manual