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Oli Glaser
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To answer the added part of your question:

Yes, the sampling rate applies to logic analysers too. Obviously the signal state will be accurately represented as it can only be 0 or 1 (unlike a DSO), but the higher the sampling rate the more accurate the timing.
For instance if you have the following:
Data:
__---_-____---____---_-___-____---____
LA Sample clock:
--__--__--__--__--__--__--__--__--
LA Display:
____----____----____----____----__

If we assume the logic analyser samples on the rising edge of the clock, you can see how it can get the timing slightly out or miss a change altogether.
You will never miss a change providing the sample rate is at least twice the data rate, but the actual timing of the changes will be less and less accurate as you approach this point.
In your case, the LA you link to will easily cope with a 300kHz toggle rate, as it's sampling at up to 200Msps, which will give you accuracy to +/- 5ns. Since the data only changes every 3.3us or so, the logic analyser will be very accurate as it can sample 666 times during this period.

To answer the added part of your question:

Yes, the sampling rate applies to logic analysers too. Obviously the signal state will be accurately represented as it can only be 0 or 1 (unlike a DSO), but the higher the sampling rate the more accurate the timing.
For instance if you have the following:
Data:
__---_-____---____---_-___----____
LA Sample clock:
--__--__--__--__--__--__--__--__--
LA Display:
____----____----____----____----__

If we assume the logic analyser samples on the rising edge of the clock, you can see how it can get the timing slightly out or miss a change altogether.
You will never miss a change providing the sample rate is at least twice the data rate, but the actual timing of the changes will be less and less accurate as you approach this point.
In your case, the LA you link to will easily cope with a 300kHz toggle rate, as it's sampling at up to 200Msps, which will give you accuracy to +/- 5ns. Since the data only changes every 3.3us or so, the logic analyser will be very accurate as it can sample 666 times during this period.

To answer the added part of your question:

Yes, the sampling rate applies to logic analysers too. Obviously the signal state will be accurately represented as it can only be 0 or 1 (unlike a DSO), but the higher the sampling rate the more accurate the timing.
For instance if you have the following:
Data:
__---_-____---____---_-____---____
LA Sample clock:
--__--__--__--__--__--__--__--__--
LA Display:
____----____----____----____----__

If we assume the logic analyser samples on the rising edge of the clock, you can see how it can get the timing slightly out or miss a change altogether.
You will never miss a change providing the sample rate is at least twice the data rate, but the actual timing of the changes will be less and less accurate as you approach this point.
In your case, the LA you link to will easily cope with a 300kHz toggle rate, as it's sampling at up to 200Msps, which will give you accuracy to +/- 5ns. Since the data only changes every 3.3us or so, the logic analyser will be very accurate as it can sample 666 times during this period.

Source Link
Oli Glaser
  • 55.5k
  • 3
  • 77
  • 148

To answer the added part of your question:

Yes, the sampling rate applies to logic analysers too. Obviously the signal state will be accurately represented as it can only be 0 or 1 (unlike a DSO), but the higher the sampling rate the more accurate the timing.
For instance if you have the following:
Data:
__---_-____---____---_-___----____
LA Sample clock:
--__--__--__--__--__--__--__--__--
LA Display:
____----____----____----____----__

If we assume the logic analyser samples on the rising edge of the clock, you can see how it can get the timing slightly out or miss a change altogether.
You will never miss a change providing the sample rate is at least twice the data rate, but the actual timing of the changes will be less and less accurate as you approach this point.
In your case, the LA you link to will easily cope with a 300kHz toggle rate, as it's sampling at up to 200Msps, which will give you accuracy to +/- 5ns. Since the data only changes every 3.3us or so, the logic analyser will be very accurate as it can sample 666 times during this period.