Connecting an external power switch using XPWR pads?

VIM3
1

I want to mount a power switch on the front of my enclosure to power the VIM3 on and off. Should I solder the wires for the external power switch to the XPWR pads on the back of the VIM3? Or should I drill a hole in the XPWR pads and use POGO pins?

Also, what type of power switch should I use? A simple on/off SPST or a momentary switch?

Thanks for any help.

2

Oops. Found the answers here:

3

I would refrain from drilling into the PCB, I think the PCB is multilayered and likely irreparable damage would result.

4

Thanks RDFTKV for that advice. I am hesitant to solder wires to the XPWR pads and I’m going to make up a small board to use POGO pins as you suggested to tschultz.

5

Yes, pads can lift from PCB and other PCB damage can result from too much heat with the iron. Depending on ones soldering skills or experience, it could be risky. And sometimes I want to keep a device unmodified, once you tin the pads, be hard to get them back to shinny.:slightly_smiling_face:

Making a POGO board is a better solution IMO and easier to undo if you re-purpose the VIM3 later. Of course it takes a bit more effort.
I look forward to your POGO board design.:slightly_smiling_face:

6

Has anyone done this yet? I am a noob and I need guidance on how to use the xpwr pads. An image of the soldering and/or pogo board that is connected to a momentary switch would be extremely helpful.

7

@Digital_Ore there is no specifics, you can solder a plain momentary switch to the pins (no polarity dependence), and it will work just fine :slightly_smiling_face:

cheers

1 Like
8

Thanks for replying. Is there an alternative to soldering the board?

9

Hi, there is only a theory on this, how it will be unknown in practice, I have not met an answer on the forum 100%.
:slightly_smiling_face:

10

:sweat_smile: I haven’t soldered before, so I am extremely hesitant but I would love to be able to swap the power switch without soldering the board as needed.

11

As they say, only at your own peril and risk

12

I haven’t soldered mine since it keeps moving place to place,
I just put a few holes in the makeshift case, and poke around with a paperclip :smile:

13

Nice @Electr1. I am researching pogo/board options. “XPWR pads” seem proprietary. As someone mentioned previously, It looks like a pogo pad so maybe I can 3D print and mount a tiny board above that area of the Vim3. ¯_(ツ)_/¯

3 Likes
14

Do you all think something like this could work?

image
image640×640 52.1 KB

15

it would work, but you need to position it just right below the XPWR pads to function properly…

1 Like
16

Could also use a piece of project board and attach the pins to it, the board itself fastened to the VIM3 with standoffs and screws. Just find an appropriate size and cut to fit.

Screenshot_20210307-064049
Screenshot_20210307-0640491072×1017 239 KB

2 Likes
17

though screwing it in, might be a bit trivial without the right tools…

18

Thanks for the feedback. Alternatively, could I modify Khadas’ vin-to-vin wire that connects underneath the Type-C port?

19

@Digital_Ore that port is for power input, you can modify a VIN cable to give your own direct DC power input,

(friendly remember: if you are not using a V13 VIM3, and apply greater than 5v on the VIN port, you will damage anything connected on the USB-C port!)

2 Likes
20

OK so I really need an alternative. I mounted a 2-pin connector and it worked but it was unstable. So, I tried my hand at soldering that connector to the board. Well, My poor attempt at soldering nearly destroyed the VIM. Is there a way to do this via GPIO (Programming or otherwise)?

Frustrated. Please help.