Ok,
I think I’ve gotten closer to where the issue is
The Anker 737 Power Bank (PowerCore 24K) - a1289 which implements Anker PIQ 3.0 and that internally supports USB PD 3.0 along with some other modes
Anker claims that the power bank supports USB PD 3.1 at 28V at 5A 140W on the output
To my understanding ( I could be wrong on some of this ) that USB PD 3.0 supports up to 20V at 5A 100W and PPS ( no good link, sorry ) mode and USB PD 3.1 supports up to 48V at 5A 240W and USB EPR and optionally AVS ( previous link describes AVS )
The Framework 180W power adapter supports AVS
USB C cables can support up to
- 5V at 3A - 15W
- 9V at 3A - 27W
- 15V at 3A - 45W
- 20V at 5A - 100W
in addition, cables that support EPR can go up to
- 28V at 5A - 140W
- 36V at 5A - 180W
- 48V at 5A - 240W
When the source ( power bank ) is able to provide more than 100W, it must support EPR
The cable that comes with Framework 180W power adapter is EPR enabled and I also have a Anker EPR enabled cable and a Hama cable that supports up to 100W
Framework cable supports upto 180W
Anker cable supports upto 140W
Hama cable supports upto 100W
When I use the Anker cable or Framework cable, the powerbank fails to negotiate.
When I enable trickle mode ( with EPR still enabled ) on the power bank, it works ( 100W only )
Enabling trickle mode drops the voltage to 20V
When I use the Hama cable ( no EPR support ), the power bank works but only up to 100W ( as expected )
I think what’s happening is that when the power bank detects the cable is EPR enabled, outputting fixed power of 140W, the Framework 16 Embedded Controller ( part of the BIOS ) is trying to negotiate with the power bank using EPR + AVS, but it fails because the power bank ( output only ) doesn’t support AVS, and the FW16 retries after some delay ( I think approximately 1 seconds ) repeatedly until you unplug the power bank
So…
it’s either Anker firmware bug, to confirm this, we’ll need another powerbank that actually supports PD3.1 with EPR + AVS enabled and outputs 140W/180W/240W to see if that works with FW16
Someone on reddit said
that these powerbanks don’t support AVS on the output
It seems like there some questioning stuff going on there. I’m going to start looking at other brands
I’m not really seeing how Framework could use the fixed power source from this power bank, where would the power go when the FW16 mainboard doesn’t need it and the battery is fully charged? This might explain that click/tick sound the FW16 mainboard makes every second it fails to negotiate.
I’m leaning more towards that the power bank doesn’t support AVS in EPR mode ( power output is fixed instead of variable like PPS ).
What the Anker powerbank should actually do is drop down to PD3.0 upon fail negotiation as it does support PPS or maybe Framework could do this on their side after a number a retries/delays?
What I’ve read here, I’m interpreting it as source and sink know when negotiations fail so they could try again but at a lower version?
Practical solution to the user? buy a USB C cable that only supports up to 20V at 5A 100W that doesn’t support EPR
I think EPR cables themselves are physically tagged somewhere to indicate to the source ( power bank ) and sink ( device like laptop, phone, etc ) to say the cable supports EPR, hence why FW16 is trying to negotiate ( as expected ) with EPR + AVS when the FW16 receiving more than 100W