After the device has powered up and ramped up VOUT, the VSET/MODE pin acts as a digital input. With a high level on the VSET/MODE pin, the device enters forced PWM (FPWM) mode and operates with a constant switching frequency over the entire load range, even at very light loads. This reduces the output voltage ripple and allows simple filtering of the switching frequency for noise-sensitive applications but lowers efficiency at light loads.