SLVSAF7C September 2010 – April 2019 TPS61251
The TPS61251 device integrates a power save mode to improve efficiency at light load. In power save mode the converter only operates when the output voltage trips below a set threshold voltage. It ramps up the output voltage with several pulses and goes into power save mode once the output voltage exceeds the set threshold voltage. During the power save operation when the output voltage is above the set threshold the converter turns off some of the inner circuits to save energy.
The PFM mode is left and PWM mode entered in case the output current can not longer be supported in PFM mode.