Is it possible to underclock a sbRIO

[SamoraJ]

Hi folks,

I have just joined a project where sbRIO 9605 was an option until it was disregarded mainly due to concerns on heat dissipation. The internal power usage according to the datasheet is ~7 W.

I would like to know if there is any way of underclocking the 400MHz CPU to render a smaller wattage.

Any hints would be really nice.

And of course I would have needed them yesterday 

Cheers

/MArcus 

[SamoraJ]

I understand that the determinism would most likely be shot to ...

And we would certainly void any warranty, but It would be nice to know if it even is possible.

Or I mean, how hard it is to accomplish.

/MArcus

[Danny_Funk]

Marcus,

What sort of power levels are you aiming for?

The internal power specifications are there to provide an upper bound. Typical applications will be lower than this spec, and are dependant on FPGA load and processor load. In general the FPGA load will have much more of an impact on the overall power consumption in comparison to under clocking the processor. 

I recommend measuring the 9605's power consumption while running your application in the intended enviroment. This will give you a better idea than looking that upper bound specs.

Regards,

Danny F

[Spex]

Hi Marcus, I want to point out that the power dissipation number listed in the user manual is the max power expected from the core NI Single-Board RIO. Actual power will depend on your actual application. One of the main factors that influences the power consumption is the complexity and amount of logic in the FPGA.

Unfortunately, I don't have a good estimate of the minimum power consumed by a "typical" application. What kind of power budget are you trying to achieve? If you can share more about your application, we (the community and NI) may be able to give you ideas if your goals are achievable and methods to achieve those goals. At this point, without knowing your end goals, I'm not sure if under-clocking would be a good method to pursue for you (if it is even possible). Are your power consumption concerns related to thermal dissipation, battery life, or both?

Do you already have any NI Single-Board RIO hardware in your possession that you can do your own benchmarking on?

Cheers,

[SamoraJ]

Thanks for the hints guys!

I only Have a 9642 board (and whatever is on the old robotics starter kit) so no new cards with the mezzanine connector.

The information about the FPGA being the greater contributer was good news although I would have thought it was the other way around.

I'll re-post if this info was not enough.

I think for now, regretedly, the sbRIO is out of the question. But we'll se.

/MArcus