Freematics Forum

Hi,

I want to bring out one design issue in your latest Freematics OBD-II emulator. The trace between the power port after diode and OBD connector pin 16 is routed through a very thin via which I believe can't pass 1A. We were using this emulator to test our devices and because of this power issue, it damaged some of our devices as device takes around 1A during boot. But in your previous emulator, the current from power port to OBD 16th pin routed directly and cables have used so no issue with that device. I strongly advise you should get your emulator design reviewed. Such an awesome emulator so can't expect this type of issue. I had to add one wire to your board to fix this issue. I can share you pictures of my analysis if you want.

Regards,
Danish

The 1mm wire is way enough to pass through 1A. This is more likely due to the power adapter (rated 1A). You can use your own power adapter with a higher rating. In some (older) cars, OBD pin 16 even has a fuse of 1A.

I think it's linked to the power adapter as well, as my emulator doesn't have problems running 1A in the wire.
But then, why did the addition of a second 1mm copper wire solve the issue? Could it be that there was a defect with Danish's model?

Maybe the additional 1mm wire helped reducing voltage drop on current surge.

Makes sense, thanks! It looks like my knowledge about electronics has to be freshened up a little...