Prototype KMPKT Dynamo DC-12V

[Kmpkt]

Hey Guys,

I've been hinting at a couple of projects I've been working on for quite a while now and I'm excited to finally reveal the first part of what I hope to be my product line. The KMPKT Dynamo DC 12V is a DC-DC solution I've been working on with Larry over at HDPlex for probably the better part of six months. I think it fills a particular need in the SFF community that hasn't been met by the current crop of DC-DC units. Without further ado, the KMPKT Dynamo:

As you can see, I've opted for a full cover heatsink not unlike the Turemetal units with what I hope is a more pleasing aesthetic than other options on the market. The heatsink has a hexagonal pattern for two reasons. First and foremost, I think it looks badass. Secondly, it allows airflow from any direction to move over the surface of the heatsink in any direction and move through. Current plans are for a metallic gunmetal finish, but nothing is set in stone. For the final design we may also thicken the heatsink to allow for taller "fins" and more heat dissipation. From the top-down view you can see the following connectors:

Left side:
- 6 pin V-in for DC input
- 4 pin SATA
- 6 pin V-out for DC flow through. This voltage will match the input from the AC-DC adapter.

Right side:
- 2 x PCIe 8 pin

As far as the selection of plugs go, the board is meant to be used for the following purposes:
- For ATX based boards in combination with a Pico solution. I personally would endorse using the HD Plex 160W DC-ATX
- For eGPU solutions where a solid and straightforward power solution is required
- For builds that want to add GPU capabilities to a Thin-ITX, Intel NUC or Mini STX
- Can be daisy chained to power more than one GPU
- Anyone who wants to eliminate the 24 pin ATX cable in their build because it is CLUNKY AS HELL (NFC S4 users, I'm looking at you <3 )

The pertinent specs are as follows:
- Rated Wattage: 300W
- Input Voltage: 16V - 24V
- Passthrough Voltage - Whatever is V-in will be passed to V-out
- System Wattage with HDPlex 160W DC-ATX: 460W
- Dimensions: 120mm long x 47mm wide x 26mm tall (2/3 the size of the HDPlex 300W DC-ATX
- Cable pinouts will match current HDPlex 300W DC-ATX. Can plug 4 pin V-in for 160 DC-ATX into leftmost 4 pins of 6 pin V-out on board

I am aiming to have this unit available by May at a price point around 70 USD. Yes I realize this makes a two DC unit solution quite expensive and AC-DC to DC-DC solution that will approach 200 USD when paired with (as an example) the HDPlex 160W Pico Style AC-DC. It will also leave you with two completely separate power units that can be used independently in future builds.

Of note, this is a proof of concept model but the first sample should look about the same. And the final product will hopefully be improved through community input.

Any suggestions on ways to improve this unit would be greatly appreciated as would comments about what you like. Anyone who is interested in acquiring one of these units can send me a PM with your contact information as I will be keeping an email list of potential customers. Cheers

Kmpkt

P.S. A massive thank you to James ( @Aibohphobia ) for all of his great work in modelling the heatsink and providing feedback that helped in the development of the unit.

 

[EdZ]

A fantastic idea, being able to separate and distribute generating components will give a lot more flexibility in case layout. I assume it has the same 16V-24V input range as the rest of the HD-Plex line?
One minor point: it might be better to call this a "DC-12V" (even though it does have one 5V line on the SATA power connector) device rather than "DC-ATX", as alone it is not capable of handling an ATX connector.

 

[Kmpkt]

I assume it has the same 16V-24V input range as the rest of the HD-Plex line?

One minor point: it might be better to call this a "DC-12V" (even though it does have one 5V line on the SATA power connector) device rather than "DC-ATX", as alone it is not capable of handling an ATX connector.

Done and done. Thanks for the suggestions EdZ.

 

[iFreilicht]

Very interesting concept, this seems like a very useful product for a lot of different niche applications. One thing that seems a little weird is that its input voltage doesn't go down to 12V. Any comment on why?

 

[aquelito]

Finally !

Would be even better if you could slim it further down.
For me, ideal size width would be around 30mm, like the ISK 110 DC board :

Molex connectors could also be 90° oriented :

 

[Kmpkt]

Very interesting concept, this seems like a very useful product for a lot of different niche applications. One thing that seems a little weird is that its input voltage doesn't go down to 12V. Any comment on why?

Yeah I tried to get this done, but basically having 12V supported apparently negates the function of the 16-24V step-down. I'd personally love to support it, but from what Larry's engineer was telling me, it's not possible to do both things on this unit.

Would be even better if you could slim it further down.
For me, ideal size width would be around 30mm, like the ISK 110 DC board :

This was about the slimmest we could comfortably get the unit. Going slimmer required having the connectors over four rows and I believe the component/PCB layout became a problem to engineer going slimmer than this. Also this unit is purpose built for the case I am developing first and foremost and these dimensions are optimal for that application. I get that a 30mm x 170mm unit would be cool however as it would allow for the unit to sit immediately next to the motherboard with the smallest possible footprint. The 90 degree plug is a very interesting idea and I considered it, but for ease of cabling and aesthetics in my case I designed it purposefully this way.

 

[Phuncz]

Oh wow this is quite the interesting product ! Combining this with an as 'tiny but powerful as possible' direct-plug DC-ATX and a properly small AC-DC would be an amazing combo.

 

[janas19]

Yes I realize this makes a two DC unit solution quite expensive and AC-DC to DC-DC solution that will approach 200 USD when paired with (as an example) the HDPlex 300W AC-DC.

This might be a stupid question, but what's the purpose of pairing it with the HDPlex 300W? I thought the purpose of the unit was to eliminate the ATX connector and that combo brings it back.

Sorry for my ignorance.

 

[Kmpkt]

This might be a stupid question, but what's the purpose of pairing it with the HDPlex 300W? I thought the purpose of the unit was to eliminate the ATX connector and that combo brings it back.

Sorry for my ignorance.

Nah it's my ignorance and typo. I meant paired with the HDPlex 160W Direct Plug. Thanks for finding my idiot error. Fixed!

 

[iFreilicht]

Yeah I tried to get this done, but basically having 12V supported apparently negates the function of the 16-24V step-down. I'd personally love to support it, but from what Larry's engineer was telling me, it's not possible to do both things on this unit.

Well I don't know what your requirements were, but after thinking about it, 12V direct regulation would probably require separate circuitry which makes the whole thing larger, and in any case you would either use the step-down converter or the regulator, but not both, which would be a waste of space. Especially considering that the only use of the unit in that case would be to provide 5V for SATA, and for that a direct plug DC/DC would be absolutely fine.

So I guess it kind of makes sense, but for the case you'll be putting this in you might want to make a short tutorial to clarify what a user can do to power it from 12V directly if they want to.

The 90 degree plug is a very interesting idea and I considered it, but for ease of cabling and aesthetics in my case I designed it purposefully this way.

Hm, I don't know. Especially considering you claim to be lower profile than the DC-ATX,

25mm tall (2/3 the size of the HDPlex 300W DC-ATX

Right-angle connectors might make a lot of sense. Unless that conflicts with the design of your case, of course. Otherwise they open a lot of possibilities and would make the unit more space efficient once cables are connected to it. For example, it would fit into the envelope in the ISK 110 that @aquelito mentioned. Or imagine it sitting in the front in an S4 Mini. Would make the cabling much less clunkier and - in my opinion - easier to deal with.

 

[CC Ricers]

This looks like a great product. Very handy also for people that wish to boost their system's capabilities with their existing 160W DC-ATX by adding this unit to their DC chain. Especially good is making it easier to add dedicated GPUs to the smallest of motherboards.

 

[EdZ]

While we can't see the actual traces that may be present, the 'gaps' between the Mini-Fit connectors and the active components beneath the 'edge' of the heatsink currently are only occupied by the mounting holes. If traces can be moved out of that area, then a short card-edge connector could be fitted in between the mounting holes. Into this, 'stub' PCBs could be inserted, with either 90° for straight-up mini-fit connectors.
This is dependant on there being free board space, and whether a short card-edge can support the current required (you can throw 685W over a 90mm card-edge at 12V, so that's a solid 'maybe').

 

[iFreilicht]

Into this, 'stub' PCBs could be inserted, with either 90° for straight-up mini-fit connectors.

Pretty sure it would be cheaper to just offer two SKUs. You could even populate them differently on the same panel, it would cost close to nothing extra.

 

[Kmpkt]

So I guess it kind of makes sense, but for the case you'll be putting this in you might want to make a short tutorial to clarify what a user can do to power it from 12V directly if they want to.

The case I am developing will have support for not just my DC-DC board, but the HDPlex 300W as well. I would be also like to build in support in for a G-Unique 12V board if they had a standard design they could send me ( @guryhwa @1461748123 ). As far as AC-DC units, it will have mounting points for the HDPlex AC-DC 300W, HDPlex AC-DC 160W. Additionally I am planning to leave a space at the bottom of the case that can accommodate either a Flex ATX or Meanwell EPP unit if someone wants to use one. Additionally I plan to provide 3D printable shroud patterns allowing you to direct an 80mm fan to blow over either of these units. As such, I plan to provide a variety of build options (and there will be MANY) for the community of users that will hopefully buy my case. My favourite build is going to be called the Wind Tunnel and is actually and idea given to me by @Aibohphobia

The other thing I am trying to get Larry to do right now is make a small unit like this to allow merging of either two 300W units, two 160W units, or one of each.

As far as 90 degree connectors, I will definitely give it some more though as I can see the appeal of having a thin full length cover plate on the heat sink with all of the connectors hidden underneath. Furthermore the whole board would still be about 120mm and with cables and plugs on either end would likely wind up being just short of 170mm which is perfect for ITX. I've already got this model out for prototyping however so this may not come to pass on this revision. Thanks for the suggestion though.

 

[|||]

This is dependant on there being free board space, and whether a short card-edge can support the current required (you can throw 685W over a 90mm card-edge at 12V, so that's a solid 'maybe').

The new FSP redundant ATX PSU will have a 700W variant with an edge connector.

 

[Kmpkt]

The other thing to consider with respect to features is price. My margins are gonna be pretty slim on this unit as it is with the relatively small MOQ I'll be going with (200 units). This means I have to keep things relatively simple. If the unit takes off, I'd love to do more complex revisions in larger quantities in the future keeping my margins about the same. This will already be something of a financial risk since I will be funding the unit completely out of pocket as well as a complimentary component I am not yet at liberty to discuss.

On a different note, I am allowed to get the heatsink done in three custom colors. I was thinking Gunmetal Grey, Black and White, but would love suggestions. Was gonna do 150 Gunmetal Units, 25 Black and 25 White.

 

[CC Ricers]

So reading the thread at /r/sffpc got me to think of a possible case with the pass-through capability of this unit. You have a dedicated 6-pin for pass through voltage, and since it's 16-24V then that output would also be in 16-24V range. However, you also have two 8-pins dedicated for GPUs, and those are converted to 12V. Is it possible in theory to use one free 8-pin GPU connector as a 12V pass-through to connect a Pico-style unit that accepts 12V only?

 

[Kmpkt]

I hadn't thought about that, but it quite possibly might be. I'll ask Larry about that possibility.

 

[Kmpkt]

Is it possible in theory to use one free 8-pin GPU connector as a 12V pass-through to connect a Pico-style unit that accepts 12V only?

If you want to use a 12V solution like the Pico PSU or the G-Unique 12V solution, this will totally work. All that you need to make sure of is that the 12V and GND lines match appropriately. So while this won't be as efficient as a pure 12V solution, those of you who already have or prefer to use a 12V Pico Solution will be able to do so.

Also I've made a last minute change to the design (95% sure we'll go ahead with this) and wanted to get some feedback from people. Basically flipped the outlets 90 degrees and grew out the heatsink. While this lengthens the unit, it also shortens it considerably. Dimensions are now 138mm x 26mm x 43.5mm. With plugs in this should nestle just perfectly alongside an ITX motherboard. Please let me know if you think this is an improvement or not:

 

[iFreilicht]

lso I've made a last minute change to the design (95% sure we'll go ahead with this) and wanted to get some feedback from people. Basically flipped the outlets 90 degrees and grew out the heatsink. While this lengthens the unit, it also shortens it considerably. Dimensions are now 138mm x 26mm x 43.5mm. With plugs in this should nestle just perfectly alongside an ITX motherboard. Please let me know if you think this is an improvement or not:

That looks darn sexy now, much better than the upright sockets! It looks like the hexagonal lines are deeper than they were before, which I think looks quite a bit better as well.