SLUAA69 July 2020 – MONTH TPS548D22
Figure 6-16, Figure 6-17, and Figure 6-18 show the startup waveforms of the lazy loading solution. The inductor current gradually increases in the negative direction and then goes into steady state. The shape of the inductor waveform looks like the normal startup of buck with sourcing current but is horizontally symmetrical. The output voltage before the startup of buck with sourcing current application is 0 V ground. Similarly, for buck with sinking current application, the output needs to be pre-biased to the target level before startup since the output is regarded as the floating ground for the load.
Figure 6-19, Figure 6-20, Figure 6-21, and Figure 6-22 show steady state, output ripple, transient response, and shutdown waveforms.