I have an Analog Card 4304 with 32 channels and Max sampling rate of 5 kS/s.
I have to measure the Voltage for CANH and CANL Dominant and recessive, my baud rate is 500000.
My question is How can I measure CANH and CANL voltage as the signal frequency is far more than the sampling rate. If not what shall i do to measure these voltages accurately? I also have a DMM 4080 with 1.8MS/s isolated digitizer.
Please provide inputs.
You are looking to achieve the functionality of an oscilloscope in a PXI Analog input module. The 4304 is intended for Power analysis application that requires high resolution (24-bit) and not a lot of digitizing speed.
Since your signal is 500kHz, the only option you have now is to use the DMM 4080 in digitizer mode at 1.8MS/s either measure the differential voltage across CANH and CANL or use a switching circuit to measure single-ended CANH in one run and CANL in the next run.
Thank you for the response.
I am currently trying it out with DMM 4080.
Although it has a digitizer, I am not able to set a triggered measurement. I want to measure the voltage at CANH or CANL on Dominant and Recessive levels. With the DMM I am able to measure the voltage but since it is not triggering properly I am not able to measure the exact Dominant and recessive voltages for CAN_H and CAN_L. I have attached the example for when exactly I have to take the measurement.
Even though the DMM sampling rate is high almost 4 times the Nyquist rate why I am not able to trigger.
Any Idea for that?
As already stated, what you're looking for is an oscilloscope with advanced triggering features.
DMM has only a handful of triggering options and none of those is to trigger on a voltage level on the measurement leads.
It is just that all that you have is a plier instead of a hammer but you want to hit the nail harder like a hammer, you could do only so much with what you have.