For most converters, the load transient response in PWM mode is improved compared to PFM mode, since the converter reacts faster on the load step and actively sinks energy on the load release. Compare Figure 9-33 to Figure 9-32. As an additional feature, the TPS6280x automatically enters PWM mode for 16 cycles after a heavy load release to bring the output voltage back to the regulation level faster. After 16 cycles of PWM mode, the device automatically returns to PFM mode (if VSEL/MODE is driven low). See Figure 8-3. Without this optimization, the output voltage overshoot would be higher and would look like the VOUT' trace. This feature is only active once the load is high enough and the converter operates in PWM mode.