We are trying to run a QSFP BERT loopback test on XEM8350 and while we run IO scans I see that the device resets because of current clamping, It looks like the default power delivery (2-5A) does not provide enough current for the same. We were thinking of ganging our power supply but clearly the barrel connector is only rated for 5A and our tests are increasing beyond 5A especially when run it for lower BER(more samples) using keysight power supplies.
Looks like Mezzanine connector is the only option which goes up to 16A, can anyone provide directions on how we supply that amount of current ? Also is powering breakout board and XEM separately a sustainable method to provide large >5A ? Parallel paths = more current ??
That seems like a lot of current for BERT tests. What supply voltage are you using? The XEM8350 can take up to 16V for the DC input, with 12V being the best option.
Thanks for the feedback, we just found out that without the fans for heat sinks these tests lead to a thermal/current runway leading to a supply reset. We were able to successfully able to complete a longer test with a table fan, I assume the recommended xem8350 fan will help even further but transceivers clearly need the heat sinks.
Additionally the current comsumption for all 8 transceivers is around 1.3W @16gbps, so yes worst case 2-3A should suffice
Indeed. Thus the rather large warning at the top of the “Powering the XEM8350” documentation that discusses heat dissipation.