The sampling frequency is divided between channels USB-6211

I use a USB-6211 DAQ card.  The jury is announced with a rate of 250 kech. / s.  I started to take action with 2 channels and could not get the frequency of sampling of 125kHz, then when I tried to make measurements on 5 channels, I could get a maximum of 50 kHz sampling frequency.  This figure of 250 kech. / s is really the sum on all channels, or is there a way to get that channel?

I have only a simple Laview program with a while loop, 1 assistant DAQ entry with 5 channels, assistant DAQ 1 exit with 1 output channel, box 'Relaxation and door' to catch a progressive input signal, a smoothing filter and graphics.

250 kech. / s is an aggregation rate as shown on the first page of the document specifications.  This means that the device has a single A/D converter that is shared by all channels under analysis.  According to th etime to the multiplexer and all time for the internal amplifier, your maximum rate may be slightly less than 250,000 / N where N is the number of channels.

Lynn

Tags: NI Hardware

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