1397 and 1398 mostly look to be pin-compatible, but the documentation I have says they're not entirely so. 1398 operates on a much different V/I which makes it fairly non-suitable for single-chip operations. I've looked into it, and the main regulator engineering would be difficult and probably pretty inefficient. A series string like we did for the R606 would be a lot easier to manage. In any case, a direct chip swap from 1397 won't work.
Kinda' what I figured I hear. Butcha' don't know till you ask.
That accounts for what Bitmain calls "voltage domains" when troubleshooting hash chip chains on their boards.
And I can see the board engineering constraints on trying to maintain packaging on your USB Compac form factor.
But if one was willing to deviate from that form factor a tad . . .
Anyway, assuming one could supply the appropriate V/I to the chip do you believe Kano's 1397 driver would communicate w/ a 1398?
Is that something you've played with?
On a different note, I found these breakout PCB's for 1397/1398 prototyping & bought 5 of them (& D/L'ed the gerber files):
https://www.pcbway.com/project/shareproject/Socket_BM1397.htmlFigured I solder them up so I could socket them into a larger board to ring out the signals (multi channel o-scope) & test w/ Kano's driver merged into cgminer for testing/tweaking.
Was also thinking that if I swapped out the USB A for a USB C connector and fed it 20V @ 3A per USB C 3.2 / 3.1 specs it might make the main LDO engineering simpler to implement w/ "off the shelf" components. That also would decrease the current handling on a USB connector.
W/ a USB C 3.2 connector an APW 9 (14.5V-21V @ 170+ A or equivalent) could be used to supply trons to the USB power bus in a USB hub versus being limited to the 5V @ 3A USB A standard.
Curious to hear your thoughts.
Pup