Rock5B USB-C PD power status on V1.42

There’s a lot of talk about USB-C PD power not working correctly, but I have not seen any info on which hardware revisions that might be affected.

I have a board marked XROCK 5B V1.42 2022.08.29X on the short top side (between audio output and fan connector).

I started using a USB-C PD 10W power supply. Using that it booted but was not stable at all.

Then I switched to a Deltaco 100W USB-C PD power supply (overkill, I know), but using that it has been completely stable.
I have an NVME attached to it but have mostly booted from microSD and eMMC.

Minimum power requirements for Rock5B are
Booting from micro-sd, emmc - 24W
Booting from NVME - 36W

Issues are when U reboot and it hangs specially when system is on nvme and when doing shut down and it doesnt completes it. It not a matter of 25w or 100w Rockchip has some glitch there.

Some boards have glitches, but not all I think.
Like I said, mine is stable since switching power supply.
It might not affect the latest revision (V1.42) but then again I have only tested one board…

LMAO!

How is it possible to come up with such insane nonsense?

@tkaiser Perhaps I worded it wrong, it is the recommended PSU from official Radxa documentation.
USB Type‑C™ PD Version 2.0 with 9V/2A, 12V/2A, 15V/2A and 20V/2A.
5V Power applied to the GPIO PIN 2 & 4.
The recommended power source capacity is at least 24W without a M.2 SSD or 36W with a M.2 SSD.

That’s not true, I’ve booted from uSD powering my Rock 5B from a dumb 5V usb source and it never exceeded 10W throughout the boot process.

Of course that’s not true. Without USB3 peripherals you’ll have a hard time exceeding 10W consumption even under full load: https://github.com/ThomasKaiser/Knowledge/blob/master/articles/Quick_Preview_of_ROCK_5B.md#consumption

I had this on WD sn850 se PCIe 4x4 SSD.
After switching to Samsung 980 (pcie 3x4) reboot became reliable

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Never seen it using more than 15W (with nvme ssd)

Certain SSDs have an ugly high peak consumption (average powermeters will not show) and as per the specs USB3 consumers are allowed to draw up to 900mA @ 5V as such with two USB3-A receptacles 9W need to be reserved for potential USB consumers (+5W for two USB2 ports).

That’s the whole reasoning for Radxa providing a 30W PSU: peripherals that need to be optionally powered in addition to the board itself.

How should such thing exist? USB-C knows two power modes that do not rely on PD and that’s 5V at either 1.5A or 3A (7.5W or 15W). USB PD defines modes above 15W.

And what most consumers don’t know: powering with 5V is a sh*t show in general since many power bricks are simply crap and only with ultra short cables and thick wires the voltage sag can be avoided. Details in this thread: Rock 5B power through GPIO pins

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