Timing resolution and Sample rate

[Qchao]

USB 6008, the time resolution is about 40 ns, and the maximum sample rate is10K/s.

What is the timing feature of USB6008.

What is the meaning the mean of time resolution? What is the sample time width?

[Qchao]

[SoarOnSon]

Hi Qchao,

Please see the link below which gives a definition and example for common DAQ terms.

Specifications Explained: NI Multifunction I/O (MIO) DAQ

From the guide:

Timing Resolution

Sample and update rates for analog input and output tasks are restricted to discrete values when using an onboard timing engine. The difference in clock periods between two adjacent rates is known as timing resolution. NI-DAQmx will coerce a selected frequency up to the next available frequency if it cannot generate the exact one specified by the user.

Example

The NI PXIe-6363 has a specified timing resolution of 10 ns. This means that it can generate or acquire data at integer multiples of 10 ns. For example, 32,000.00 Hz and 32,010.2432... Hz are two adjacent frequencies, as their clock periods are 31.250 µs & 31.240 µs, respectively. To find the next available frequency, add or subtract the timing resolution to a known clock period.

Josh

Applications Engineer

National Instruments 

[Qchao]

Hi Josh,

I am sorry, by reading the links you mentioned. I am getting more confused. Could please give a specific example of USB 6008? All I would like to know is the time span of each acquisition, and sample rate in 10K/s, 1K/s. Could you draw a timing graph to demonstrate this?

Thanks a lot!

Qinchao

[SoarOnSon]

Hi Qinchao,

The graph that you posted describes what you looking for. With a 10 kS/s sampling rate, you will acquire data in 0.1ms intervals from one rising edge of the clock tick to another, and each data point will be acquired at the respective clock tick at the sampling rate. 

Josh

Applications Engineer

National Instruments