This issue will stay updated for any hardware bugs found in development of v0.9 board until v1.0 hardware is ready. If you think you've found a bug in the v0.9 hardware, please open a separate issue for discussion, and this document will be updated once that discussion is resolved.
Problem: 1.8v-capable SDHC (UHS-I and newer) cards won't work in Linux [#2]
Root cause: microsd SD2 powered by NVCC_SD2, but needs a constant 3.3V
Workaround (software): add device tree property no-1-8-v
Proposed v1.0 solution: supply microsd SD2 VDD with VDD_3V3
Problem: voltage sag on initial power causes pmic to shut down [#3]
Root cause: excessive inrush current on VDD_3V3 due to aggressive decoupling for PCIe
Workaround (hardware): don't stuff C125-127. Change reflected in released v0.9 BOM.
Proposed v1.0 solution: add load switch with inrush-limiting for PCIe 3.3V rail
Problem: Type-C port will not take host role [#4]
Root cause: can't communicate with U9 (swapped sda/scl pins)
Workaround (hardware): cut and jump to pull up resistors R19/R20 (see linked issue)
Proposed v1.0 solution: fix scl/sda pin swap
Problem: Advise in BQ27426 notes is not followed [#5]
Root cause: U12 pin BIN shorts to Vss when battery is used
Workaround (hardware): cut and jump R51 to configure as BIN pulldown to GND (see linked issue)
Proposed v1.0 solution: don't include Q1 and configure R51 as pulldown
Problem: Battery over discharge protection circuit does not work [#6]
Root cause: disabling discharge with IO on charger did not work as intended
Workaround: use a pack with integrated protection circuits.
Proposed v1.0 solution: add a FET to properly disconnect battery on fault
Problem: Some out-of-spec but common mPCIE cards do not fit [#7]
Root cause: cards interfere with components on the board
Workaround (hardware): replace mPCIE connector with 2041262-1
Proposed v1.0 solution: update BoM
This issue will stay updated for any hardware bugs found in development of v0.9 board until v1.0 hardware is ready. If you think you've found a bug in the v0.9 hardware, please open a separate issue for discussion, and this document will be updated once that discussion is resolved.
Problem: 1.8v-capable SDHC (UHS-I and newer) cards won't work in Linux [#2] Root cause: microsd SD2 powered by NVCC_SD2, but needs a constant 3.3V Workaround (software): add device tree property
no-1-8-vProposed v1.0 solution: supply microsd SD2 VDD with VDD_3V3Problem: voltage sag on initial power causes pmic to shut down [#3] Root cause: excessive inrush current on VDD_3V3 due to aggressive decoupling for PCIe Workaround (hardware): don't stuff C125-127. Change reflected in released v0.9 BOM. Proposed v1.0 solution: add load switch with inrush-limiting for PCIe 3.3V rail
Problem: Type-C port will not take host role [#4] Root cause: can't communicate with U9 (swapped sda/scl pins) Workaround (hardware): cut and jump to pull up resistors R19/R20 (see linked issue) Proposed v1.0 solution: fix scl/sda pin swap
Problem: Advise in BQ27426 notes is not followed [#5] Root cause: U12 pin BIN shorts to Vss when battery is used Workaround (hardware): cut and jump R51 to configure as BIN pulldown to GND (see linked issue) Proposed v1.0 solution: don't include Q1 and configure R51 as pulldown
Problem: Battery over discharge protection circuit does not work [#6] Root cause: disabling discharge with IO on charger did not work as intended Workaround: use a pack with integrated protection circuits. Proposed v1.0 solution: add a FET to properly disconnect battery on fault
Problem: Some out-of-spec but common mPCIE cards do not fit [#7] Root cause: cards interfere with components on the board Workaround (hardware): replace mPCIE connector with 2041262-1 Proposed v1.0 solution: update BoM