Indiegogo Campaign + Edge Developer Samples

For buying an external USB PD PSU and cable :
When you say “up to 20V”, and looking at the five USB PD Power Source Profiles below. Is profile 4 or 5 supported, or are both profiles supported (behind the USB Type-C ports) ?

  • Profile 1 (Default Startup): 10 W (5 V @ 2 A)
  • Profile 2: 18 W (5 V @ 2 A -> 12 V @ 1.5A)
  • Profile 3: 36 W (5V @ 2 A -> 12 V @ 3A)
  • Profile 4: 60 W (5 V @ 2 A -> 20 V @ 3 A)
  • Profile 5: 100 W (5 V @ 2 A -> 20 V @ 5 A)

Yep, both the USB-C ports support PD features, and the voltage can up to 20V. We recommend 18W+ PSU for the Edge to match more different application scenarios. Btw, our ROM set the voltage as 12V as default.

Thanks for responding on a Sunday. Is 18W+ also for Captain + Edge combo ?

What does this mean exactly?

I get that the majority of your forum users currently have not the slightest idea how expensive good USB-C chargers are that are fully USB PD compliant.

So what’s your take on powering Edge-V? Will you provide a 12V/3A PSU with USB-C cable?

Are you aware that you need also ‘special’ cables for Profile 5? The only USB-C and USB PD compliant charger supporting Profile 5 in this household is f*cking expensive.

IMO the interesting questions are

  • are users aware that USB-C compliant chargers are expensive?
  • What is your target power budget? CPU consumption is irrelevant (since already known – check my ODROID-N1 ‘review’) but it depends on consumers connected to the board.
  • If only USB PD compliant powering can be used (hopefully not) the question is whether your use case is fine with 36W?
  • If the boards accept any 12V input as power source then how is situation with current limiters?

It means that the Edge Rom responsible for PD, starts off the handshake negotiations with the PSU, with Profile 2. Instead of with the usual startup default of Profile 1. Profile 1 would probably underpower the Edge.

Yes. PD ROM + intelligent PD USB cable + USB PD PSU. You need special cables for USB PD, not just for PD profile 5. Otherwise the startup handshake will use the fall back scenario.

Expensive is always open to interpretation.
All I’m after is find out the highest PD profile that the Edge will negotiate at startup, and then find out the lowest PD profile number I can get away with safely (3, 4, or 5) for a Captain + Edge Max + 256GB NVMe SSD, and a Captain + Edge Max + 512GB NVMe SSD.


I know but this doesn’t change the fact that normal ‘special’ cables aren’t enough for Profile 5. Those 100W capable cables are even more expensive.

And in the meantime I took one of the many 12V PSUs with the usual 5.5/2.1mm barrel plug that are lying here around anyway and do testing with RK3399 and fast NVMe storage :slight_smile:

@Gouwa can you please comment on this? What does this mean when it’s about to connect the Edge with a low-spec USB-C charger only capable of 5V? Will stuff like this happen again:

As Tigger replied, the Edge compliant full USB PD features and the voltage can go up to 20V, and we just config the handshake voltage as 12V (Rockchip recommed for RK3399), surely, the devlopers can set to 20V if they want.

Have to note that, many USB-C PSU with 20V output can also suppor the 5V/9V/12V/15V outputs, so the 12V hanshake voltage will works for all USB-C PSU

Of course, to let the USB-C PSU to output voltage higher then 5V, should use USB-C cable with CC PINs, and good quality to carry higer Ampere current.

As I known, there don’t have 100W USB-C PSU available in the market at the moment, actually, even Macbook Pro just use a 61W PSU, and 30W for 12 inch Macbook :wink:

A 12V PSU with 5.5/2.1mm works for Khadas Captain.


I think a 18W PSU will work, sure thing is that an expensive 100W PSU can also work out :blush:

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Well, the one I use is 87W rated. And with a normal USB-C cable charging my MacBook Pro takes a lot longer.

Anyway: your recommendation of 18W is not sufficient for people connecting USB peripherals. So I would better adjust this now since you’ll have a lot of forum users later complaining about instabilities/crashes (it’s easy to test and the tests have already been made)

In a few years this will have changed (when there’s more than one USB-C compliant charger capable of at least Profile 3 lying around in every household). But today USB-C will just add another ‘nice’ problem source for devices that do not need to be charged but are required to run from a probably limited current provided by inferior USB-C gear as it’s common today.

Funnily symptoms will look like software issues (‘I recently installed $something and now my board crashes’) so have fun with the additional support efforts :slight_smile:

Well, my question was what will happen if users buy an Edge and connect it to their USB-C charger only capable of 5V (USB-C chargers not implementing USB PD are a thing, it’s allowed to have chargers only providing 1.5A or 3A at 5V). What will this average user experience then? The Edge not starting?

I already asked this but to no avail: will you provide an inexpensive and dumb 12V/3A PSU with USB-C cable (not that I would recommend such a thing since it’s violating USB specs and can be used to fry all normal USB-C devices around).

For anyone eagerly wayiting to power his Edge with a fully compliant USB-C charger: take some time to read through the caveats first: :rofl:

See my last link. Recommended USB-C chargers that do not set your equipment on fire start at $35.

You will probably simply avoid USB-C at all then and use a 12V PSU with barrel plug instead. At least now that no costs are disclosed. I wonder whether Captain + Edge Max will remain below the 100 bucks barrier…

The problem with going for the barrel plug is that it won’t fit in a standalone Edge.

Sure. So time to do the research to get the least expensive USB-C charger (+35 bucks? 40?) and an appropriate cable able to signal negotiation of more than 5V. See @Gouwa’s comment there too:

Given that no prices are disclosed yet and I don’t believe Edge and Edge-V will cost just 10-20 bucks to compensate for the huge amount of costs for all the needed accessories (PSU, power cable, heatsink and fan) I’m out already anyway :slight_smile:

Just got notice that two more RK3399 thingies are on its way from China: NanoPi M4 (using USB-C but able to be combined with an el cheapo dumb 4A charger – we’ll see how well this works) and Rock960 EE (Ficus). Not sure how powering works there since ‘96Boards Enterprise Edition’ powering specs are quite confusing.

It’s not about thermal pads. It is not about the efficiency of passive cooling and passive options to provide full equipment operation throughout the range prescribed in the surrounding temeprature (conditions). By the way, your tests have confirmed this clearly. Even small forced increase in air supply, dramatically reduces the overall temperature by 30-35 degrees. And this despite the comfortable conditions of the test. The lack of reaction (changes) in temperature by changing the position of the Board (set the Board vertically) also showed that indicating the radiator is clearly not intended for use in passive cooling systems. Its design is not designed for use in passive systems. This means that we used a part with a price of 10 , and the result was obtained as from the price of 2 (the figures are conditional and show inflated costs, with a minimum result). Its working area is only on the common surface of the radiator and the inner surface is not working. About the noise from the fan, using the correct equipment there is not any noise.


So what?! Did you ever looked into the datasheets of the stuff you’re dealing with? This is a SoC not an animal or a human being. This thing is fine being operated at +80°C. There’s no need to have a chip running at the temperature level of your skin.

All I want is maximum performance at reasonable consumption figures, no noise and no moving parts and all at a competitive price. So no fan whatsoever especially not with a design that’s made to be inefficient and is overly expensive at the same time. And I honestly don’t care if the SoC is dead after 10 years instead of 100 since already in 5 years any SoC we use today is not in use any more anyway since obsolete (the ARM world moves too fast).

It seems all it’s here about is stuff that looks nice and pleases enthousiasts (people who love fans, fancy looking enclosures, leds blinking and such stuff). Not my area of interest…

It was about the efficiency of two different cooling systems (passive and active) for the entire declared range of operating conditions of the equipment. For your specific operating conditions (and load used), perhaps the simplest passive system is sufficient. Only you have forgotten that the equipment under discussion will be used not only in such comfortable conditions as yours, but will also work in much more severe conditions (in the case and / or with high ambient temperature, etc.). Accordingly, the manufacturer (Khadas) take care not to repeat the previous mistakes and (I hope) strive to develop all the necessary components in advance. Which will ensure guaranteed operation of the equipment in all modes. For those who will use the equipment in light conditions, the first element of the cooling system - a passive radiator-may be enough. For those who will make the most of the equipment-need a second element, a ventilator (with automatic temperature control).

Don’t twist the facts. The difference of 30 degrees I showed you as an indicator of low efficiency of the passive system and high susceptibility to instability at work. Try to place your equipment in real operating conditions, such as in a car (or ATM or other real working device) and at 40-50 degrees of ambient air. And load the system with real work, so that all components (CPU, intensive exchange over the network and with media, etc.) would work. Then evaluate the efficiency of the cooling system.

Why should I even try to do this? If I would do ATMs or car entertainment systems I would look for stuff that is available in industrial temperature range (Edge is? – happy to learn that)

I know the maximum load my RK3399 devices get (yeah, including heavy networking stuff which does not increase temperatures BTW) and I want to operate them at reasonable costs, without moving parts and noise and with no wasted energy.

All I would get with Edge or Edge-V is an insufficient heatsink for my use case (since constructed to be only efficient when used with mounted fan) relying on a method of insufficient heat transfer from SoC to heatsink (thermal pad) so this use case simply won’t work with Edge or Edge-V or I would need to spend at least 20 bucks on something I don’t want or start to mill my own heatsink which I also do not want.

TL;DR: No appropriate passive cooling option provided for Edge/Edge-V which is not a problem since I probably can’t afford operating Edge/Edge-V anyway (at least I don’t want to spend 40 bucks just on a PSU per board). But fortunately this really is no problem at all.

Do you already have an idea about the target price?

I don’t really understand the point of releasing more and more boards, if you can’t even support 2 boards, if you look at the software support, i do believe that Khadas has one of the worst supports.

Even on this forum, if you need an answer, you have to wait for few days, and that is not something that we expect.

I believe that most of people that use sbc’s, buy them because of low power consumption, if i need 100w, it’s better to search for an x86 machine, it is plug and play, you don’t need to worry about os and driver support.

A lot of stuff was promised when Vim1 was released, and you failed to deliver, we can thank to other companies and people who have contributed for free for all the things achieved for S905/X soc’s.

I don’t believe Khadas edge will have competitive price, even if the price was correct, you’ll need to invest a lot of money for accessories.

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