Tab5 Power up sequence

scroggyg

I have 2 Tab5 which I am powering through the Port A I2C connector. They won't power up when power cycled. IF I connect the USB C to aa hub, wait a few seconds, they then power up and stayed powered up. I have previously powered Tough boards through the I2C and it all worked fine.

felmue

Hello @scroggyg

M5Tab5 port A is powered through a switch (U26) which when turned on lets SYS_INT5V through to SYS_EXT5V. The switch is enabled via EXT5V_EN coming from one of the port expanders (U6).

In other words, M5Tab5 cannot be turned on via port A as initially the switch is off.

See schematic here and/or the backside of M5Tab5.

Thanks
Felix

scroggyg

I assume then the correct way to do this would be to use ExtPort2 and connect up to 12V through HVIN?

felmue

Hello @scroggyg

yes, either that or provide 5V via 5VIN.

Thanks
Felix