Test and Measurement Forum

4227 External Trigger

Post any questions you may have about our current range of oscilloscopes

4227 External Trigger

Postby BSI » Wed Apr 13, 2011 3:45 am

What type of trigger can the EXT input work with on a 4227 ? TTL (0-5V) digitial inputs? analog?
Thx.
Laurent
BSI
Newbie
 
Posts: 0
Joined: Wed May 12, 2010 3:15 pm
Location: Canada

Re: 4227 External Trigger

Postby ziko » Wed Apr 13, 2011 2:49 pm

Hi the 4227 has a +/-20V range, there is a 10 bit DAC so you can have a granuality of approximately 40mV.

Hope this helps.
Ziko

Technical Specialist
ziko
Zen Master
Zen Master
 
Posts: 1705
Joined: Fri Dec 01, 2006 10:03 am
Location: St Neots

Re: 4227 External Trigger

Postby BSI » Wed Apr 13, 2011 5:21 pm

Thx Ziko . I had missed it on the specs. So presumably it will detect a TTL level change.
L.
BSI
Newbie
 
Posts: 0
Joined: Wed May 12, 2010 3:15 pm
Location: Canada

Re: 4227 External Trigger

Postby ziko » Thu Apr 14, 2011 9:39 am

Your welcome, I don't think it is in the spec. You should be able to detect TTL no problem, you just put your voltage trigger level at the appropriate level.
Ziko

Technical Specialist
ziko
Zen Master
Zen Master
 
Posts: 1705
Joined: Fri Dec 01, 2006 10:03 am
Location: St Neots

Re: 4227 External Trigger

Postby BSI » Thu Jan 24, 2013 1:46 pm

Hi,
The 4227 specs indicate for the Ext Trigger that
- Voltage range ±20 V
- Threshold range ±150 mV to ±20 V

Based on previous discussion in this thread, with a 10bit ADC, one would expect 40mV granularity for the trigger level.
What does the +/- 150mV " threshold range " indicate then? Aren' t the two figures in contradiction?
Thx.
L.
BSI
Newbie
 
Posts: 0
Joined: Wed May 12, 2010 3:15 pm
Location: Canada

Re: 4227 External Trigger

Postby ziko » Thu Jan 31, 2013 6:32 pm

Hi you have a point, my initial post I forgot to mention that there is a +/-150mV threshold where the trigger does not work. This is just due to hysteresis in the circuitry.

The specification lists this :

http://www.picotech.com/picoscope4227-s ... tions.html

Sorry if that caused any confusion.
Kind regards
Ziko

Technical Specialist
ziko
Zen Master
Zen Master
 
Posts: 1705
Joined: Fri Dec 01, 2006 10:03 am
Location: St Neots

Re: 4227 External Trigger

Postby BSI » Fri Feb 01, 2013 7:50 am

Thx Ziko for the clarification, it is helpful, and did not cause trouble. :D

Still on the triggering topic with a 4224 or 4227 :

- if I want to acquire on Channel 1, and trigger out of channel 2 ( or vice versa), can the range of the triggering channel be set differently than the other channel's (acquisition channel in this example), or do I only set the range of the acquisition channel, the trigger channel range being set internally according to the trigger level ?

- if I want to acquire on Channel 1, and trigger out of channel 2 ( or vice versa), are both channels being acquired, and as a result potientialy (4227) halving my max sampling freq ?

Thx.
L.
BSI
Newbie
 
Posts: 0
Joined: Wed May 12, 2010 3:15 pm
Location: Canada

Re: 4227 External Trigger

Postby ziko » Fri Feb 08, 2013 11:30 am

Hi sorry haven't been in the office lately,

It depends on what you want to do, you can trigger and acquire the data on one channel and that way you can have the maximum sampling rate. If however you wanted to acquire on one channel and trigger on another channel then you need to enable both channels, this way you can have two different voltage ranges one for you acquisition and one for your triggering. The maximum sampling rate will drop the more channels you enable.

Hope this helps.
Ziko

Technical Specialist
ziko
Zen Master
Zen Master
 
Posts: 1705
Joined: Fri Dec 01, 2006 10:03 am
Location: St Neots

Re: 4227 External Trigger

Postby BSI » Fri Feb 08, 2013 5:09 pm

Ok. Thx.
Laurent
BSI
Newbie
 
Posts: 0
Joined: Wed May 12, 2010 3:15 pm
Location: Canada


Return to USB PC Oscilloscopes

Who is online

Users browsing this forum: No registered users and 0 guests