ZHCSGE0B June 2017 – January 2019 TPS53681
PRODUCTION DATA.
There are two levels of undershoot reduction protection (USR) (USR1/USR2) selection. USR1 enables up to 3 or 4 phases and USR2 enables up to the maximum number of phases. The initial setting of the USR threshold is to start with USR1 and USR2 as OFF, and then to meet the load insertion transient requirement by lowering the threshold to enable pulse-overlap during the load transients.
For this design, VOUTA USR1 is selected as 240 mV and USR2 is selected as 300 mV. VOUTB USR1 and USR2 are selected as OFF.