Duet3 in SBC

[YYCSparks]

Hey guys,

I just moved from Standalone to SBC, do I need to power the Pi separately once I add the 24volt power supply to the Duet? Or will the board power the Pi?

[Phaedrux]

You should power it separately.

[YYCSparks]

@Phaedrux Okay, thank you. I thought once the Pi was connected to the Power Supply it would get what its needs from there but I will add the Rpi power supply back into the mix.

[Phaedrux]

Previous versions of the Duet 3 Mainboard 6HC allowed for the Duet to power the SBC, or the SBC to power the Duet. More modern SBCs (e.g. RPi 4) needs too much 5V power, especially with a screen, to make it sensible to supply from the Duet. Similarly the spare 5V power budget on the SBC may not be sufficient for the Duet. In addition some SBCs require >5V on the 5V rail to not give an under voltage warning.

Due to this, the jumpers for 5V power between the Duet and SBC ('5V -> SBC' and 'SBC -> 5V*') are not populated on this board revision.

[dc42]

To add to what @Phaedrux said, the new version 1.02 Duet 3 MB6HC board accepts up to 48V input. To keep costs reasonable, we have had to reduce the maximum current available on the 5V rail, because 48V to 5V step down regulators that support high current and meet EMI regulations are difficult and expensive to engineer.

[YYCSparks]

@dc42 @Phaedrux Thanks guys I added a Power Supply for the RPi