MinimOSD without extra battery


I would like to add FPV to my 3DR IRIS. I found a Camera and a transmitter, both work with 5 Volts. Is it possible to connect them with the MinimOSD and power everything from the Pixhawk, without any extra battery? I know it is not recommended because of possibly noise on the video signal, but my question is if it is possible at all and how?

Thanks in advance,

Hi Udo,

I wouldn’t recommend to demand more power from the Pixhawk, if you have the consumer version of Iris there is a power cable for the gimbal, the voltage is from the battery, so you can use a BEC or a voltage regulator to convert the battery voltage to 5V to power your 5V camera and transmitter.

Thought I’d add to this thread instead of starting a new one.

Is it absolutely necessary to use a separate battery to power the video tranmitter with the MINUM OSD setup? (Something about needing a second ground?)

I’d like to run power to my Fatshark transmitter using a 12v connection from my power distribution board.

So then in other words, the same battery that is powering the whole hexacopter, including of course the Pixhawk, is also powering the video transmitter.

I have done this in the past with other OSD’s and all worked fine.

But I read somewhere that a separate ground is needed (separate battery?) to keep the MINIM OSD from burning up? And a second battery provides a second ground?



You don’t need a second battery. You can either power the analog side of the MinimOSD from the flight battery (3S only) or if your vtx and camera both support 5V, you can theoretically power both thru the Pixhawk, although - as Rogelio wrote - it’s not recommended.

Please check the documentation: … ion-guide/

Thanks Stefan.

The reason I was asking is that in the DIY Drones forums someone was saying that a second ground absolutely HAD to be used or the Minum would get burned up…but maybe that was prior to v1.1?

And from previously seeing the diagram at: … ion-guide/

And seeing that a second battery is used in both situations, well, I assumed the second battery was being used for the second ground…after all, why have a complicated 2-battery/power wiring setup when one power source will suffice?

Please check the attached wiring diagram. Will that work?

Anyway, thanks so much for clearing that up.

Also…is there a good wiki page for programming the Minum with the FTDI cable and software / firmware? Looked but can’t really find one. Like, are there MULTIPLE firmwares to use? Does the 3DR Minum OSD come pre-programmed with a firmware? Or is it “blank”?


I only see a battery in the wiki, not a second battery :slight_smile:. If your vehicle runs 3S, you can use the main battery. If your vehicle runs more than 3S, only then you need a second battery - or a BEC which provides the 12V - I have the latter in my bigger 4S copter. The “burning up” was another problem - in an old version, when you powered the analog side with 12V, the system would get very hot and some burned out. But that was IIRC a design flaw in the regulator circuit and wouldn’t have been prevented with a second (12V) battery. It would have gotten just as hot…

Regarding your drawing, you should route the ground also through the OSD, as the video signal is against ground. And you forgot to power the analog side, unless you are planning to use the solder bridges as explained in the Wiki.


OK…right…there is only one battery (I just figured it was a second battery, as per the “2nd ground” references).

And OK…I see what you are saying by the rest of your reply…and I assume this wiring would work… … e_Diagrams

Jup, that should work.