SLVSG98B February 2023 – March 2024 TPS628301 , TPS628302 , TPS628303 , TPS628304
PRODUCTION DATA
To maintain high efficiency at light loads, the device enters power save mode (PSM) at the boundary to discontinuous conduction mode (DCM). This event happens when the output current becomes smaller than half of the ripple current of the inductor. The device operates with a fixed on-time, and the switching frequency decreases proportional to the load current as shown in Figure 7-2. Calculate as:
In PSM, the output voltage rises slightly above the nominal target, which can be minimized using larger output capacitance. At duty cycles larger than 90%, the device does not enter PSM and maintains output regulation in PWM mode.