We do not support these for now. This product is for people who rely heavily on USB-A and want the best performance. However, USB-PD Profile 1 is defined as 10W (5V/2A), which the charger can certainly deliver. We will likely include it in future chargers.
We picked the 7 to 17V range because those chips worked best for circuit optimization, load compensation, and integration with charge controllers.
However, we are actively reviewing options. One option is to include it in future chargers.
DC barrel jacks with an external diameter of 5.5mm, and an internal diameter of either 2.1mm or 2.5mm will work. They're sometimes referred to as "coaxial power connector". The IEC standard is "60130-10 A", but many listings won't include that specific name. Often the description is just of the ID and OD -- "OD: 5.5mm, ID:2.1mm/2.5mm".
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