Trigger jitter when using AUX IN

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rph
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Joined: Tue Jun 16, 2015 4:06 pm

Trigger jitter when using AUX IN

Post by rph » Mon Nov 02, 2015 1:09 pm

I'm using a PicoScope 6404C together with a pulse/delay generator for the triggering. (PicoScope 6.10.18.1052)

It seems there is an problem with the trigger input using the AUX IN channel.

Using the AUX IN as trigger source, the signals jitter by approx 6 ns, but the channels don't jitter relative to each other.
Ashampoo_Snap_2015.11.02_13h33m47s_003_.png
Trigger using AUX IN
When I use channel A as trigger source, I don't see the jitter:
Ashampoo_Snap_2015.11.02_13h33m10s_002_.png
Trigger using channel A
I tested this with two different pulse/delay generators with different TTL signal voltages (0.5 V to 2 V amplitude) and the standard of 5 V.

Hitesh
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Re: Trigger jitter when using AUX IN

Post by Hitesh » Mon Nov 02, 2015 3:23 pm

Hi rph,

The AUX IN input is digital and uses a comparator circuit which then indicates if a trigger has occurred. It is not linked to the sampling on the input channels, hence there will be jitter.

To reduce jitter it is advisable to use one of the input channels as the trigger channel.

I hope this helps,
Hitesh

Technical Support Engineer

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