How to measure Rise Time of a power supply

[ofer_o]

Hi,

I have the following task and I'd like to share my though with you as to how to handle it...

The task is to set a new voltage to a power supply and measure the rise time  (depending on the voltage step, it could be from 10ms to 500 ms)

1. creating a 3 stage execution task (sequential)

2. In the first one, I define the input voltage of my MIO AI and the Start task control, here I also define how many samples to take.

3. In the second stage I call a dll that set a new voltage to my power supply.

4. in the 3rd stage I put the array were all the data is written and a transition control that calculate my rise time.

Does that make sense?  Any comments?

Thanks

[CoastalMaineBird]

I don't see anything wrong with your approach; however, I'll throw out a few thoughts:

If you could tie the sending of the change-voltage command (in your DLL) to the START TASK command for DAQ, you could reduce the variability in the time between the two events. Maybe that's important, maybe not.

Can you set the voltage via some LabVIEW code, rather than a DLL?

You might or might not want a variable sampling rate - if you expect 10 mSec, you might want to sample at 10 kHz to catch the 1% difference between 10.2 and 10.3 mSec. But if you're expecting 500 mSec, you could sample at 200 Hz to catch the 1% difference between 500 mSec and 505 mSec, thereby saving data space and processing time. Maybe that's important, maybe not.