Radxa X4 External Power

#1

Hello,

I have ordered multiple Radxa X4 boards. I plan to connect a 4K 20fps camera to the board via the Ethernet port. Therefore, I assume PoE will not be usable.

Before the boards arrive, I want to order a suitable power supply. The board will be installed on a motorcycle, and although the power line provides 12V, I plan to use a relay in the system. To prevent possible damage from back EMF and other external factors, I intend to use the isolated galvanic power module shown below. This module fully isolates and re-regulates the motorcycle’s 12V power supply, outputting a clean 12V.

My question is: can I safely power the Radxa X4 with the following adapter? The adapter provides 40W (12V / 2.3A)

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#2

This looks like OK, but you may need to consider the stability of the connection, heat dissipation, and the vibration.

#3

This galvanically isolated adapter provides sufficient current and power, and is industrial-grade, minimally affected by factors like vibration and heat.

If it is compatible, where and how should I connect it? As far as I see, the Radxa X4 has no dedicated external power port. To avoid damaging the GPIO pins, I will not supply power through them. Since the camera will be connected via Ethernet, I also cannot use POE.

So, where and how do I supply power to the board using this adapter?

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#4

I mean to ensure good contact when connecting with X4, X4 generates a lot of heat and is only a consumer-grade product.
Connect the 2pin next to the type-c interface for power input

image
image.jpg1397×947 501 KB

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#5

Okay @ryann,
I will directly connect the output of the fully isolated 12V to 12V dc-dc converter module (whose link I shared above) to the two pins you specified on the Radxa X4 board.

Thank you.

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#6

I take note the very helpfull advice thats on offer here and also remark, that isn’t it very common for an 12v header to be present and thankfully incorporated into and found on most Single Board Computers?

You should note that an 12v power supply via an coventional auto-motive style battery, is probably the most reliable form of uninterrupted power for an SBC, proving that lead-acid battery technology doesnt fail and it still has an edge over today’s rivals.

I seem to recall that an 12v automotive style battery, upon examination testing and experimentation proved to be one of the most reliable forms of UPS (uninterrupted power supply) available for an SBC…

Regardless that’s great advice pointing out the whereabouts on the X4 board of the 12v header, i also downloaded the image and carefully took note of its presence for future reference, aswell it would be great to hear about the X4 motorcycle project that’s in mind.

X4 on an motorcycle? It all sounds very intresting.

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#7

Hello @eric1.

I’m glad you’re interested in my project. When I shared parts of it on a motorcycle forum, it also attracted a lot of attention.

Automotive batteries are of course extremely reliable, but they are exposed to high ripple and EMF interference from components like the alternator, starter motor, and relays. So in this case, I want to galvanically isolate the 12V vehicle power and supply it to the X4 that way.

The project was initially developed for fingerprint reading on touring motorcycles, but now it targets high-resolution iris recognition under harsh weather conditions. The hardware interface consists of many layers: the main control board (STM32), iris comparison module (Radxa X4 and optimized camera), relays, voltage adjustment modules, I/O ports, etc. There are many parameters including special 850nm LED illumination, reflection reduction/prevention filters, and modulated imaging for security if needed. Despite all this consideration, environmental stress factors remain a huge challenge.

There is already a small STM32 microcontroller in the system for electrical monitoring and management. It controls everything alone. The Radxa X4 will run the iris recognition program and use the special NIR camera I mentioned above. I’m in contact with the world’s leading companies about this camera and have ordered several potential options. When the Radxa X4 successfully completes iris recognition, this information will be transferred via GPIO pins to the waiting STM32. Evaluating the situation and safely activating the ignition is the STM32’s job. All software and hardware must be synchronized.

I don’t know how successful I will be. But I want to try. I’ve spent about $10,000 on R&D, and it could all be wasted at any moment. The project might also fail.

Back to the point, I’m about to order the galvanically isolated power adapter. Thanks to everyone interested. Greetings from Turkey.

#8

It’s even more intresting?

I’m aware the voltage on motorcycle alternater, stator, generator arrangements, is ‘well err’, somewhat peaky,

It is however in simplicity, an dynamo arrangement.

I’m an qualified motor-cycle mechanic incidentally and know full well that without regulation, that stator will pump out voltage no end, more revs of the engine, then more volts in the circuit and an crude 12v regulator is normally used to control this almost endless alternator voltage surge.

Infact, it’s incredible to see the amount of electrical component damage that gets done, should the voltage regulator on an automotive, ever pack-in.

However, your cleary dealing with very sensitive electrical requirements regards you’re X4 project and your doing an great job judging by your chosen equipment.

This, if you want my uninitiated motor-cycle engineer opinion?

It sounds like, please correct me if I’m wrong, that your setting up facial recognition equipment onto the bike to defeat theft and that’s an great idea, if I’m correct, particularly when motorcycle theft is an real issue.

I can honestly say and from experience, that such innovative equipment would certainly be popular, especially should it render the machine in-operable if it fails to recognise the genuine operator.

Such equipment would almost certainly have an market within the motorcycle fraternity and also be highly welcome by those in authority, who see vehicle crime, quite rightly, as an very serious issue.

Why, even insurers would queue to endorse such an product, thus the money you’ve already spent could be an very wise and sound investment.

I’ve seen motor-cycle insurers endorse padlocks, trackers and other anti-theft devices, even offering premium discounts to owners who purchase these recommend anti-theft items.

I wish you all the best and can see you clearly are, but an small step from success, please keep us up-to-date with your project, this if your copyright and patent details allow you too, because your project is not only innovative in its use of todays computer equipment and technology, which is rather conspicuously non-evident on modern vehicles, but since it’s perhaps if I’m not mistaken, to counter theft and crime, then it’s an obvious and keen public intrest topic aswell.

Wishing you well my friend with your X4 motorcycle project, wishing you well…!!

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