Charge pump with fixed-ratio output
The Maxim Integrated MAX861IUA+T is a charge-pump voltage converter that delivers a fixed ratiometric output: either -Vin (inverting) or 2Vin (doubling), selected by the pin configuration. No external inductor is needed — just two or three capacitors for the flying and reservoir stages. The 50mA output current handles low-power analog rails, op-amp supplies, or bias voltages in portable and board-level designs.
Housed in an 8-uMAX/uSOP (3mm × 3mm body), the MAX861IUA+T is a surface-mount part suited for dense PCBs. No synchronous rectifier is integrated, so efficiency is moderate — typical for a simple charge pump of this class.