cRIO 9474 Output delay time

[Monza]

I'm going to use the cRIO 9474 digital output modlule to control a high speed/high current driver. The following data is stated in the manual: Output delay time (full load): 1 μs max. Full load is 1A, the current output for the driver is only 10mA. Is there any chance that output delay time will be longer then 1us with such small load (10mA)? Will there be any jitter? My switching frequency is going to be around 200-300kHz.

Best regards,
Per

[Ricardo_SR]

Hello Per,

There is a bit on confusion about the 1μs that we spec on the manual.  That time or delay time is just the time that it takes the signal from the cRIO Backplane to the MOSFET in charge of turning the channel ON or OFF.  That time won't change depending on the load.  That means that the gate will start turning ON or OFF at the same time no matter what the load is.

What changes is how long it takes for the line or channel to get to the desired voltage value.  That will change depending on the load but shouldn't be too significant.

We don't spec that because that a value that depend on your load.

Hope this answers your question.

Ricardo Santa Olalla

CompactRIO Product Support Engineer

National Instruments.

[Monza]

Thank's Ricardo!

I assume that the channel will use longer time to rise to the desired voltage value with increasing load?

Per