SNVSBK9C November 2019 – September 2020 LM63635-Q1
During light load operation, the device is in PFM mode with DEM. This provides high efficiency at the lower load currents. The actual switching frequency and output voltage ripple depend on the input voltage, output voltage, and load. The output current at which the device moves in and out of PFM can be found in Section 9.2.4. The output current for mode change depends on the input voltage, inductor value, and the programmed switching frequency. The curves apply for the BOM shown in Table 9-3. At higher programmed switching frequencies, the load at which the mode change occurs is greater. For applications where the switching frequency must be known for a given condition, the transition between PFM and PWM must be carefully tested before the design is finalized. Alternatively, the mode can be set to FPWM.