1 Introduction

Better load transient performance and higher efficiency are always key design factors in portable applications, and the operation mode (FPWM or Auto Mode (PFM or PWM)) is selected based on system conditions. Generally, both FPWM and Auto Mode have pros and cons, and Auto Mode is widely used when high efficiency is required under light load conditions. However, Auto Mode has a relatively slow response compared to FPWM when the output load changes rapidly between light and heavy load conditions.

Figure 1-1 shows the typical application circuit of the TPS62810 configured to provide a 1.8V output from a 3.3V input. The MODE or SYNC pin is used for the mode selection, and the TPS62810 operates in FPWM since the MODE or SYNC pin is tied up to VIN. If the MODE or SYNC pin is pulled low (to GND), then the TPS62810 runs in Auto Mode.