lixnig
Newbie level 5
Hello, Everyone.
I am troubleshooting a problem with a carrier board with a controller on-board. There are two revisions of this carrier board with two different controllers due to the original controller being discontinued and replaced with a new mostly identical controller. I have confirmed with their engineers that the controllers' are identical in timing specs.
When I plug the new revision board into the main board, I receive no output. I have tracked the problem down to a control signal having a very long rise-time compared to the original board. So, I setup a makeshift test of the carrier board using a devkit I had lying around. Using this setup, the rise-time is what I would expect it to be, so I have concluded that the timing is in agreement with the specs. The time to output of the old revision is ~65ns. The new revision is over 220ns.
So, my question is, what could cause such a large difference? My initial reaction is that the RC characteristics of the new revision board are causing this, but I'm really more of a digital/software engineer than an analog guy, so I'm hoping someone can point me in the right direction.
Lixnig
I am troubleshooting a problem with a carrier board with a controller on-board. There are two revisions of this carrier board with two different controllers due to the original controller being discontinued and replaced with a new mostly identical controller. I have confirmed with their engineers that the controllers' are identical in timing specs.
When I plug the new revision board into the main board, I receive no output. I have tracked the problem down to a control signal having a very long rise-time compared to the original board. So, I setup a makeshift test of the carrier board using a devkit I had lying around. Using this setup, the rise-time is what I would expect it to be, so I have concluded that the timing is in agreement with the specs. The time to output of the old revision is ~65ns. The new revision is over 220ns.
So, my question is, what could cause such a large difference? My initial reaction is that the RC characteristics of the new revision board are causing this, but I'm really more of a digital/software engineer than an analog guy, so I'm hoping someone can point me in the right direction.
Lixnig
