This paper presents a hierarchical tree-structured control digital low drop-out (DLDO) regulator using hierarchical tree-structured control (HTSC) which enhancing the binary search algorithm. HTSC not only achieve fast chasing time, but also can lock output voltage to target voltage precisely. To improve the transient response, status-dumping mechanism (SDM) is utilized to store the thermal code generated by HTSC. During transient response, this thermal code is promptly converted into SDM control signals to regulate power MOS, with a settling time of 0.23us. In addition, Freeze Detector (FD) can reduce quiescent current and improve current efficiency during steady-state operation, measured current efficiency is 99%.
