/fp3-notes

Random notes about my fairphone experience.

Fairphone 3 notes

SoC and main board

The Fairphone uses the Qualcomm Snapdragon 632 Mobile Platform. Not much documentation is available to the public, the best available from the vendor is a product brief. According to Wikipedia, these are "pin and software compatible with 625, 626 and 450". A few more details can be found about the older Snapdragon 626. Wikichip has a few more details

Alongside a Samsung multi chip package (MCP) lovingly named KMRH60014A-B614, providing 4 GiB of LP3DDR volatile memory combined with 64 GiB NAND with an eMMC 5.1 interface.

Top portion of the main board PCB of a Fairphone 3

Test Points And Pinout

The following are measures and probes done against an unpowered, turned off but battery plugged, or a powered device. Running without any display or other peripherals.

The labels are arbitrarily assigned, just as a reference. Measures and reasoning or net assignment are educated guesses, at the very best. Do not rely on any of this data.

Labeled Test Points Top

label connected to bat plugged power on comment
A BAT 4 0V 0V GND
B BAT 4 0V 0V GND
C
D
E
F BTN 4 0V 0V power button
G BAT 1 4.2V 4.2V
H BAT 1 4.2V 4.2V
I 0V 1.32 - 1.36V (takes a few seconds to rise after power on)
K 0V 0V EDL
L 0V 1.78V EDL
N FP 4 0V
O FP 9 0V
P FP 3 0V
Q FP 2 0V
BTN 1 0V 0V volume down button
BTN 2 0V 0V volume up button
BTN 3 1.78V 1.78V

Labeled Test Points Left Side

label connected to bat plugged power on comment
R 0V 0V GND
S 0V 0V UART RX (?)
T 0V 1.78V UART TX
W 0V 0V GND

Similar devices

Other Android devices that use the same Qualcomm platform (non of which has a LineageOS port so far, it seems):

  • Asus Zenfone Max M2 ZB633KL
  • Honor 8C
  • Zeizu Note 8
  • Motorola Moto G7
  • Motorola Moto G7 Play
  • Motorola Moto G7 Power
  • Xiaomi Redmi 7
  • Xiaomi Redmi Note 4
  • Lenovo K10 Plus

Links and references

The iFixIt teardown provided lots of details about the internals and served as a good starting point.