2. Block diagram of a PPG subsystem using discrete power-supply devices. 1.8-V SMPS Circuit Using a nanoPower Buck Converter The following circuit based on the MAX38640A nanoPower buck converter (Fig.

1. Block diagram of a typical PPG remote-patient vital sign monitor. This dc-dc power-management integrated-circuit (PMIC) design is used to regulate three output power-supply rails for use in a ...