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0 pointsssl-31y ago0 comments

Pinecil V2 is specified to be 88w -- less than 100, but not very far off.

And with a (simple) firmware change and the appropriate 28v EPR charger, it can do 140w.

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ssl-3OP1y ago· 2 in thread

I goofed up. It can do 126w (not 140w) with the appropriate charger.

https://wiki.pine64.org/wiki/Pinecil#Power_Chart

omgtehlion1y ago

Yes, and your link shows that the power delivered is dependent on tip resistance (which can vary with temperature). Hence pinecil --or almost any other usb-c iron-- cannot control real power delivered.

And you cannot fix this with updates, no firmware can magically grow buck converter with beefy inductor inside the iron...

ssl-3OP1y ago

Yes, and yes. And absolutely not.

The chart is intended to show values for both kinds of tips that are usable on a Pinecil. V2 tips have a lower resistance, by design, and either style can be used with either handle.

Temperature is not indicated, although resistance can vary with temperature. But then: Temperature is never indicated for power of soldering irons. If you want to begin a trend of producing this data and filling this void, then by all means do so. Let me know how I can help.

And no, we absolutely do not need a buck converter to accomplish heating a resistive element in a circuit, nor to use PWM to modulate the average power dissipation of this circuit. (A buck converter can be used; sure! But E=IR and P=IE anyway.)

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