Powering MatrixPortal M4 Through Screw Plugs?

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Woodside
 
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Powering MatrixPortal M4 Through Screw Plugs?

Post by Woodside »

Hi,

If I wanted to power and drive more matrices than what the MatrixPortal can push alone, could I use a beefier 5V power supply to power both the panels AND the controller via the terminals normally used for out-going power?

Basically, are those screw terminals current-throttled or would pushing 5V into it (rather than from it) fry the board?

Thank you!

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dastels
 
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Re: Powering MatrixPortal M4 Through Screw Plugs?

Post by dastels »

It's possible. The matrix power terminals are connected directly to 5v/gnd on the MatrixPortal. But there's the caveat. It's also connected directly to the 5v on the USB-C connector. There are no protection diodes as it is designed for power to flow into the board through the USB-C connector and out through those screw terminals. There's no way to protect the USB connection from power being supplied through the screw terminals. It will work fine as long as USB isn't connected. If you forget and plug in USB while power is on the screw terminals, you might get trouble. If you need more power for your matrix(es) use a separate power supply and continue to power the MatrixPortal via USB. Connect the ground wire from the matrix to the GND screw terminal, but leave the 5v screw terminal unconnected, and it would be a good idea to insulate the end of the 5v wire from the matrix.

Dave

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Woodside
 
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Re: Powering MatrixPortal M4 Through Screw Plugs?

Post by Woodside »

dastels wrote:It's possible. The matrix power terminals are connected directly to 5v/gnd on the MatrixPortal. But there's the caveat. It's also connected directly to the 5v on the USB-C connector. There are no protection diodes as it is designed for power to flow into the board through the USB-C connector and out through those screw terminals. There's no way to protect the USB connection from power being supplied through the screw terminals. It will work fine as long as USB isn't connected. If you forget and plug in USB while power is on the screw terminals, you might get trouble. If you need more power for your matrix(es) use a separate power supply and continue to power the MatrixPortal via USB. Connect the ground wire from the matrix to the GND screw terminal, but leave the 5v screw terminal unconnected, and it would be a good idea to insulate the end of the 5v wire from the matrix.

Dave
Hmm, but the board itself should be fine as long as I didn't try to plug in the USB port while it's powered that way? I'll see about just having two power supplies but if this is an option I'd like to at least give it a shot.

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dastels
 
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Re: Powering MatrixPortal M4 Through Screw Plugs?

Post by dastels »

Yes, 5v from the screw terminals is the same as 5v from the USB connector as far as the MatrixPortal is concerned.. Again, just be careful not to connect both at the same time. Something will not like it. Probably whatever the USB is connected to.

Dave

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