How much power is this pin rated to deliver? I’ve built a mezzanine that works flawlessly on a DB410C, but on Hikey960 the 1.8V line collapses to 0.3V with the mezza attached. When I feed 1.8V externally from a lab supply, the devices on the mezza that need 1.8V start working again and the lab supply shows to draw only 11mA.
In the next version of the mezza PCB I’ll make sure to add a separate 1.8V supply, but it still seems weird that this is neccesary.
According to the spec it should be good for 0.1A but I’m sceptical this was
tested during the design phase for these boards if only because early
software images for both versions of hikey shipped with the 1V8 output
disabled by default.
How accurate is your supply’s reading at low current?
Not sure, it’s a €100 30V run of the mill Chinese lab supply. It reads 11mA. I checked with the supplier of the panel that is actually taking this current a while back. Just found the email and they said 14.2 mA. So I guess they’re right 
Anyway I popped off an unused 2.8V supply off the mezzanine PCB and fitted a 1.8V, ran a tiny wire and I’m up and running. Next version of the PCB I’ll take this into account. Of course if HiSilicon or anybody else can give any advice on how it should or shouldn’t be possible with the onboard 1V8 supply, that would be most welcome.
Is it possible that your device needs an initial high current to start up?
FYI: hardware manual actually claims up to 150 mA and acknowledges that 96boards only requires 100 mA, so they’re specifically claiming to exceed required spec by 50%.
