Communications for power delivery solutions

A protocol can specify a power-sourcing voltage range that indicates power sourcing capabilities. Additional power sourcing capabilities can be communicated using voltage variations within the power-sourcing voltage range. A power-sourcing device (102) can provide power to an external power-sinking device (104) over a wired connection containing a plurality of wires (110). A voltage control circuit (106) can be configured to drive a voltage over a wire of the plurality of wires (110). Processing circuitry (108) can communicate, using the voltage control circuit (106), first power-sourcing capabilities to the external power-sinking device (104) by setting the voltage over the wire to a value within the power-sourcing voltage range. The processing circuitry (108) can also communicate, using the voltage control circuit (106), the additional power sourcing capabilities of the power-sourcing device (102) using voltage variations on the wire, the voltage variations maintaining voltage on the wire within the power-s