SLUAAE4 May 2021 TPS563211
3.3 Summary for Bench Test Results
With On-Time Extension triggered, when loading is added to 3 A, the maximum duty cycle drops. This is caused mainly by the power loss of the RDS(ON) of the HSFET and LSFET, and the power loss of the DCR of the external inductor.
With frequency foldback, VIN_VIN is lowered by decreased fSW, as shown in Figure 3-5.
Figure 3-5 Frequency Foldback at Dropout
(VOUT = 5 V)