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Custom USB splitter solution for M3

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Hi all,

After using the USB Y-cable splitter for a while I wasn’t happy with 500mA charging current limitation and started to look for the USB splitter/hub that can output more than 500mA. Surprisingly, I didn’t find anything on the market.

A few weeks back I started designing one (I'm a hardware engineer) and thought I'd share my solution:

Tiny device plugs to M3 front USB port and splits the power and data in to two USB connectors (charger port and data port).

Charger port has a charging port controller chip. It will recognize the connected device and output maximum charging current (limited to 2.1A by the design).

The data lines connected straight to the second USB connector for Flash drives only (Sentry Mode/Music). It has at least 100mA current left on it, which is more than enough to run the flash drive.

Would like to get your feedback on this.

Capture_2.JPG Capture_1.JPG
 
This thing is pretty slick, but do we know how much power its ports can actually deliver? There are currently no specs on Jeda's web page.
Yeah, that would be nice to know. I did find this in their FAQ section, but it's still short on details.

What’s the charging distribution like on the Model 3 USB Hub?
The electronics offer a split design which will make sure that the driver side USB-A won’t lose charge even if the other 4 USB ports are in use. When using both USB-A connectors to charge and only one extra connector for the storage device (dashcam) the passenger side USB-A will lose under 0.4A of power. The only time the passenger side will experience a significant charge drop will be when all ports are being used to charge devices simultaneously. But even in this scenario, the driver side won’t lose charge.
 
Yeah, that would be nice to know. I did find this in their FAQ section, but it's still short on details.
Aha. Sounds like the left hub port is directly connected to one of the car's ports, and the remaining hub ports share the second port. So you'll have the same power limitations as if you were using a regular hub in one of the ports today.

The OP's proposed splitter could potentially provide more power from a shared port (but I'm not sure if Tesla's ports can actually deliver up to 2.1A?).
 
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I`m in a process of making small batch (15 boards ) for initial run. The first copy's should show up next week. Planing to 3D print enclosure for now. If there is enough interest I will order tooling (mold) for custom enclosure and use ABS material.

If any of those 15 boards are unspoken for, I would be thrilled to be a (paying) tester - case or no case. Please feel free to PM me if you’d like another tester!
 
Any reason you're bothering with a charging controller at all? Just short the DP/DM lines together and you'll get 1.5A and it simplifies everything quite a bit. Pretty sure higher power flash drives are going to need more than 100mA, anyways.

EDIT: Also makes this whole thing completely passive. In fact you can do that with cables already.
 
Any reason you're bothering with a charging controller at all? Just short the DP/DM lines together and you'll get 1.5A and it simplifies everything quite a bit. Pretty sure higher power flash drives are going to need more than 100mA, anyways.

EDIT: Also makes this whole thing completely passive.
In fact you can do that with cables already.

True, I can short DP/DM and use only USB DCP 1.5A without any components and make it passive.It depends what you want.
Since the power budget is more that 1.5A I better use it all.
My design covers Apple 2.1A, Samsung 2A, and USB DCP 1.5A charging protocols.
I can set the output current to any number (up to 2.5A). Also, its a automotive grade part with over-current protection and auto recover. Another benefit, if you short the charging port output it will not kill the flash drive on the other port.
 
Way ahead of ya dude. Well, in making it work for me (and not bothering to make more, LOL)
usb.jpg

The gray cable is just a captive USB A cable a few inches long. Then it routes the data to the port with the USB drive, and power to both ports. The charging-only port has resistors to identify it as a 1A charging port for iPhones.
 
True, I can short DP/DM and use only USB DCP 1.5A without any components and make it passive.It depends what you want.
Since the power budget is more that 1.5A I better use it all.
My design covers Apple 2.1A, Samsung 2A, and USB DCP 1.5A charging protocols.
I can set the output current to any number (up to 2.5A). Also, its a automotive grade part with over-current protection and auto recover. Another benefit, if you short the charging port output it will not kill the flash drive on the other port.

Not sure you can guarantee it won't brownout the other port if you short the supply. The Tesla ports have their own overcurrent too, so all you need is to get past the limit of the Tesla port and it'll trip as well.

Also, pretty much all devices support DCP at this point. Samsung 2A isn't used almost anywhere besides on old stuff, and Apple devices respect DCP. Kind of a waste of a TPS2511-Q1, isn't it? ;)

Current limit accuracy is also another issue... with +/-10% accuracy, there's no guarantee you're going to get something that works across all ranges without accidentally hitting the Tesla built-in limit. My concern is that flash drives are definitely not all under 100mA, so if you set the current limit too high on your 2511 you don't have any method to dial that down if you have a current-hungry flash drive.