Feedback on Uno Q Power Input (VIN) Design

Official Hardware UNO Family UNO Q
1

Hello, this is my first time posting, I recently ran into a roadblock thinking that the UNO Q had certain capabilities, when it does not. I'm hoping to make the case for robust powering options out of the USBC port in a future version of the board.

There are many threads discussing the troubles of getting peripherals or the Arduino itself properly powered, most notably this one: USB Power disabled, if using VIN Power pin

Here are 2 others:

USB Power disabled, if using VIN Power pin

No voltage on 5V pin when powered via VIN

The community is looking to apply the UNO Q in a variety of ways, and given a "universal" USBC on the board, the board should be expected to negotiate power OUT of the Arduino when requested by peripherals. If it can accept 5V 3A from a standard USB, it should also handle 5V on the VIN port as well.

UNO Q USBC power output could be a manual override, which implies that the user assumes the risks associated, or there should be a more straightforward method of inputting power for this use case.

I am building a fixed-wing airplane, and I want to stream data from my Intel Realsense D455 down to a base station over wifi. The Realsense streams data in Gbps, and also requires USBC power input. My idea was to power the Arduino via its VIN port, and power the camera by plugging it into the UNO's USBC. The UNO Q is a great choice because it's light, cheap, and has the capabilities I need.

After reading these posts, I see that isn't designed for this. This is detrimental because now I have to add a USB splitter, and we're already weight constrained. It also makes the UNO Q's VIN port less useful for non-legacy applications, or useless if using a USB hub is an option for you. I think the UNO Q needs a direct method of powering such that it can negotiate and deliver USBC power to ancillaries.

Especially for robotics applications, where space or weight constraints are real problems, any professional user shouldn't be expected to use a USB hub to attach a camera module. In a future version I would love to see changes to the VIN port that allow for USBC output power. I think it would be a great improvement to the product. Thanks!

2

I use Vin all the time but I do not power peripherals with the Arduino, it was not designed nor specified as a power supply. A few mills is OK.

3

In what way can any change to the VIN pin make this or any board able to deliver more than a few ma to any sensors or other small current devices?

Unless I am misunderstanding you this is a non-starter of an idea.

4

Good to know that lightweight ancillaries work!

5

That's a fair point, but the UNO Q has already made more innovative leaps than this. I'm far from an elecE, but if the VIN pin cannot handle large currents then a dedicated power connector would be nice. Something like the DC barrel on the legacy UNO. I'd assume the step-down on the VIN pin could be used to regulate the same voltage range down to 5V for USBC.

I'm not saying it's currently feasible, but it would be nice for a new version of the board.

6

I do not disagree. I have some WeMos R1 D1 boards that include a 1A switch mode power supply on the same footprint as an UNO, along with an ESP8266. They are now obsolete, but they still work well.

More power can be made available, but it will likely increase the footprint. Then the question becomes what to provide: 3V3, 5V, maybe 12V, and at what current levels. The most practical solution I have found is to use an external power supply sized for the application.

When using an external supply, I disconnect the 5V lead in the USB cable. I use a cheap USB hub with switches; in this case, the manufacturer simply switches the 5V line rather than the D+ and D- signals, so data and ground remain connected so programming works and terminal work.