[SOLVED] What is the absolute, drop-dead, maximum input voltage for the GoPiGo?

Another data point: (but no motors and no multi-core video pattern recognition)

My philosophy for Carl is to manage load to find limits and stay out of trouble. Perhaps, if you want to try really pounding a Pi4 get another one and put it on your desk. The GoPiGo3 board will not supply enough 5v to drive the Pi4 to the max, but will serve up enough for exploring lots of topics.

You can also just add a usb-c powerbank to the Pi4 power connector and use the existing batteries to power the GoPiGo3, no?

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I really want to post a picture of Charlie connected to a 12v car battery with huge-honkin’ jumper-cables as a goof. Not really connected, but to make it look like I’m powering Charlie off a gigantic DieHard!

That’s my question! What happens if I connect something to both power connectors?

More better goodness for longer. (Saw that in some forum post long, long ago …)

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How do I go about creating the load-map. Perhaps yours is a sufficient guide that (at the very least) gives me relative magnitudes?

Put Charlie up on a pedestal, strap a multimeter between the battery and bot, and start plugging and unplugging, driving and not, sensing and not, speaking and not, etc.

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But only when Carl gets off. Don’t you have him “up on a pedestal” already? :wink:

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Interesting observation:
I have Charlie sitting on my desk with a fresh set of batteries installed. With that, the battery voltage returns 9.6.

If I attach a True and Authorized Raspberry Pi-4 Power Supply to the USB type-C connector, the “measured” battery voltage jumps to 18.something!

Obviously, the battery voltage hasn’t jumped by that amount. I suspect I’m going to have to take a look at the GPG driver board schematic and propose a hardware change. :wink:

nice way of giving me a heart attack!!!


r u sure? usb-c allows it.

actually, I think Also remember matt saying something about that happening and to ignore it.

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USB-C allows a lot of things, including video.

The Raspberry Pi supply itself spec’s at “5.1V (DC) 3.0A”

Even with the GoPiGo battery connector removed, it still reads 18+ volts.


Translation: The “battery voltage” is only trustworthy if nothing else supplying power is connected.


This thread:

. . . has a link to the voltage regulator data-sheet, and according to that, the absolute drop-dead max voltage is 45 volts for the garden-variety version.

Ergo, an 18v battery should work.

Ah, yes, but… but no biggie at 18v…

The DMP3017SFG power switch has a 30v breakdown voltage and who knows what the caps are rated at, but Matt didn’t seem to be too worried about being slightly over the 14v limit.

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Here is one of Matt’s post on powering the GoPiGo3:

and a more specific “The absolute maximum voltage should never exceed 14.5v.”:

and this one also - he expressed concern about someone exceeding the 14.5v limit:

So it would appear the answer is:

The absolute, drop-dead, maximum input voltage is 14.5v


I can accept that, but I wonder why?

I guess that GoPiGo schematic is coming out of the drawer again. :wink:

Not sure if this big cap is on the input side?

Perhaps this is it?

Screen Shot 2020-03-19 at 9.06.02 AM

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Definitely possible. I have to look at it myself - when I get back from visiting friends.

I’m seriously considering unsoldering that cap and moving it to a different place on the PCB attached with a twsted pair so I can attach my Pi-4 without having to completely re-engineer the 'bot.

Or you could consider getting the newest board

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Yea, all the way to Russia, right? :wink: