A hundred watts is a cable question
100 W means 20 V at 5 A and nothing else. Five amps needs a USB-C cable with a chip in it, so with the lead that came with your phone the same board tops out at 60 W.
Where the number on the box comes from
The CH224K is a 100 W part. That is not a separate capability; it is 20 V times 5 A, the highest rail it can request multiplied by the most current USB Power Delivery 3.0 will carry over a cable. Take away either factor and the number goes with it.
Three things have to line up:
- The charger must offer 20 V — see what the charger must offer.
- The charger must be a 100 W charger. A 65 W brick at 20 V is offering 3.25 A, which is 65 W, however good the cable is.
- The cable must be rated for 5 A.
The cable is the part people forget
USB-C limits an ordinary cable to 3 A. To carry 5 A, a cable has to contain a small chip — an e-marker — that tells the charger it is thick enough. Without that chip, a 100 W charger and a 100 W trigger board still give you
20 V × 3 A = 60 Wand no warning that they have. Everything works; you simply cannot draw the last forty watts.
Laptop cables and cables sold as 100 W or 240 W generally have the e-marker. The lead that came with a phone generally does not, and the thin white one in the drawer almost certainly does not.
What the board itself will carry
This is the honest gap in the specification. The chip is a 100 W part and the negotiation is a 100 W negotiation, but 5 A has to flow through this particular 26 mm of board and out through a 3.5 mm screw terminal, and neither of those is something the chip's datasheet has anything to say about.
So: treat 5 A as a figure to verify rather than assume. Run the load you actually have, let it settle, and put a finger near the terminal and the traces. Warm is normal; too hot to hold is a message. For anything continuous, leaving plenty of margin costs nothing — most of what people build with these boards lives at a couple of amps, where none of this is close to a limit.
When it does not work
Something in the path is limiting. In order of likelihood: the charger has hit its wattage, the cable is a thin charge-only lead, or a screw terminal is not tight on the wire. Measure at the terminal with the load running, then at the far end of your wiring, and compare.
You mostly cannot by looking. Cables sold for 100 W or 240 W charging, and cables that came with laptops, generally are; thin cables that came with phones and anything sold as charge-only generally are not. If 5 A matters to you, buy a cable that states its rating.
The chip is rated for it and the negotiation will ask for it, but what the board itself can carry is set by its copper and its screw terminal, not by the chip. Treat 5 A as something to verify with a thermal check on your own board rather than as a specification, and keep continuous loads well below it.
Three measurements that between them name every way this board disappoints, and the order to take them in.
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