Embodiments include apparatuses, methods, and systems related to an assist circuit that may be coupled to one or more components of a memory system to selectively lower a supply voltage that is delivered to the component. For example, the assist circuit may be coupled to a plurality of bitcells (e.g., register file bitcells). The assist circuit may selectively lower the supply voltage delivered to the bitcells during at least a portion of a write operation and/or during an inactive state of the bitcells. Additionally, or alternatively, the assist circuit may be coupled to a read circuit to selectively lower the supply voltage delivered to the read circuit during an inactive state of the read circuit. The assist circuit may include a control transistor coupled in parallel with one or more diodes between a main supply rail and a supply node of the bitcells and/or read circuit.