A little postscript: you can ignore the proximity to the ram. The ram has to be placed closely to the SoC itself simply for signal reasons. Given this isnt a full scale desktop pc the memory controller is in the SoC itself, and needs a rather short path to the ram chips. they most certainly do not have any direct connection to the power inputs
Rock5B Smoke after power on with Passive HDMI-VGA converter
You could try supplying fixed voltage, since the PD-chip is fried. Probably you can still use the board supplying 12v fixed.
Out of curiosity, were you using a barrel jack to USB-C adapter when this happened?
Others reported the same issue (FUSB302B burning) with broken jack-to-USB-C adapters that send the barrel jack’s voltage to the wrong pins (only GND and VBUS should be connected, but some adapters erroneously connect CC as well).
Currently, I do not have access to multimeter. For replacing the FUSB032, I do not have equipment for that as well. Allnet has already replied to me for the return of this unit.
No, I used the official Radxa USB-C cable that came with the Official Radxa USB power PD 30W (https://shop.allnetchina.cn/collections/rock5-model-b/products/radxa-power-pd-30w) they are both brand new. I also tried to charge my phone with that and it works fine.
Here are the output voltage of the Radxa USB PD 30W
- OUTPUT: 5V/5A 9V/2A 12/2A 30W
I chose this official power supply to avoid all issues but that did not seem to work on my case.
I do not have other power supply for this unit, that’s why I bought the official Radxa Power PD 30W.
Please don’t blindly put 12v on this board. Stuff like this will fry the board. The board should always be initialized at 5v, just as any of the acceptable power sources(dumb USB brick or pd Bd) would do. Anything higher WILL destroy stuff.
Out of curiosity @AXdaruser since you got the got the RMA approved already, could you try powering the board on using 5v on gpio 4/6? These kinds of failure are actually quite interesting as to how far the damage goes. The manufacturer will not report on this issue for good reason
I will try the power it on via 5V over the week end as I am away from home.
There’s two https://www.monolithicpower.com/en/mp8759.html in the power path. The 1st deals with the input voltage (4.5 – 26V) at the USB-C receptacle to transform it into sane 5.1V for USB3, HDMI, etc. and the 2nd then transforms this into 4V to feed this into the PMIC.
This is where you risk frying the board… Bypassing the buck converter…
The barrel is connected to the input of a buck converter and, according to Radxa, the board can take up to 20V.through it.
OMG, this forum is such an insane collection of nonsense/BS.
Directly above someone explained there are two buck converters and even linked to schematics.
It’s perfectly fine to provide up to 26V to the USB-C connector. And 5V is the voltage expected at the GPIO pins (and the 2nd buck converter).
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Correct. And if one directly supplies 5V on the GPIO pins, one bypasses the first buck converter…
I have asked about supplying 24V to the board, but it was advised not to do so. Not more then 20V. See here:
Give that radxa states the possibility to supply power via GPIO Pin 2+4 explicitly on their own wiki to the product, I would say that is normal usage and thus covered by acceptable use.
Apart from that tkaiser is right. (and I wasnt aware that a direct fixed voltage power supply was a possibility, just read up on it)
To clarify up on this.
My suggestion to power the board up using alternative power paths(in this case GPIO) exactly has the point of bypassing the first(and in this case broken) buck converter. It doesnt matter, since as tkaiser rightly summarized there’s a secondary on the board.
My whole reason of asking the OP to do this was my curiosity about whether the whole board was fried or whether we actually got some quality and the board has secondary protections against power surges etc(as in a smoked primary buck converter doesnt kill the entire board but rather has a protection that prevents the rest of the board from getting the spike).
As an addition to satisfying my curiosity this could also help in the rough investigation on the source of the problem that occurred here. The OP states that it went up in smoke when he attached a hdmi to vga converter. This is something that shouldnt ever happen, which leaves me to believe the source of the fault could have either been a short caused by dust et al, a fault in the power supply or maybe even static electricty that got transferred from the op when attaching the adaper, even though I highly doubt that.
If however the board works beyond the known-broken circuitry that would at least hint at an acquittal for the hdmi adapter used.
For the GPIO power, currently I do not have 5V 6A DC supply only 5V 2.5A RPi PSU. Not entirely sure if it is possible for me to test.
I can confirm no dust on the HDMI port of Rock5B nor HDMI-VGA converter, anti-static precautions have been observed. I had used other SBC’s before this one. The same HDMI-VGA adapter continues to work on my Laptop and Raspberry Pi 3B+ SBC.
You don’t need 6A. As per (I assume they are one and the same) @tkaiser s page here: https://github.com/ThomasKaiser/Knowledge/blob/master/articles/Quick_Preview_of_ROCK_5B.md
The RPI power supply should be plentiful for a quick test run
I tried to power on the device via 5V on GPIO pins and it does boot loop, cannot get anything on the display except (No signal to detecting input to no signal again, loops). Will get a serial console later and check output. After this, will schedule the return to allnetchina. I need to look for cheap ways to return this as the fee for return is expensive on where I am at.
Hm. Taking in account that there is no such thing as “passive hdmi vga adapter” - I believe that adapter tried to take voltage it needs to run from HDMI pin 18, which lead to frying the HDMI slot. As for protection circuit that usually prevents it - i don’t think it was either in adapter or rock5 (even x86 iGPU not always have them)
That’s why you don’t use “passive” adapters.
Update: The busted IC has been replaced by allnet.
All is good now.
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