One example discloses an apparatus for charge recycling between a first power-domain operating at a first voltage and a second power-domain operating at a second voltage, including: a first power-delivery circuit configured to supply the first voltage to the first power-domain; and a second power-delivery circuit coupled to receive power from both the first power-delivery circuit and the first power-domain; wherein the second power-delivery circuit is configured to supply the second voltage to the second power-domain.