01-23-2021, 04:16 PM
(01-23-2021, 03:47 AM)Ralim Wrote:(01-22-2021, 07:29 PM)Timpanogos Slim Wrote: Out of curiosity, i plugged my Pinecil into my Anker model A2322 60w USB-C PD brick with a 2M USB-C charging cable that was sure advertised as being capable of 60W PD, and says so on it, whatever that is worth. I bought these for my Pinebook Pro originally. Plugged the brick into my kill-a-watt power meter.
The display shows 15v on it, and the KAW shows it drawing 28W. Just to see if it was holding back unless/until it needed the juice i put the tip inside a spare "V6" style 3d printer printhead heatsink and held it in front of a fan. It struggled and continued to just get 15v.
Is this a bad cable maybe, or perhaps this is a firmware issue? This pinecil is from the 2nd production run, just received today.
Hello,
This is expected behaviour. If you look at the details on that power brick it is only 45W on the usb-c port. ("60W" = 45W type-C +15W type-A).
As the soldering iron is basically a resistor its current draw is proportional to voltage.
As such it will not select the 20V range if the adapter cannot provide sufficient power (60W) for that voltage range.
And it will instead pick the highest voltage it can, without overloading the power adapter.
As most usb type-C adapters will shutdown very rapidly on overcurrent (or some just up and break), it instead takes the safest option of only using what the adapter advertises as in spec.
Also tiny note; usb-pd only goes up to 20V.
I'll grant you that a careful reading of the label does indicate that it maxes out at 45w either via 15v or 20v.
But it only drew 28 watts at 15v, and never switched up to 20v.