Design of a One-Chip Ultra Low-Dropout CMOS Voltage Regulator
Xiao Jian · Microelectronics & Computer · 2009
Design and realize a ultra low dropout voltage regulator with maximum 500mA output current,analyze the circuit structure and the subcircuit design.A novel internal frequency compensation technique is presented,which can implement the use of low equivalent series resistance(ESR)output capacitor,thus improve transient response and reduce the cost greatly,and accurate overcurrent protection is realized.Test result from a verification in Vanguard 0.5μm CMOS technology proved the feasibility of this method,the measured typical dropout voltage is 100mV,operating voltage range is 2.5～7V,output overshoot voltage is less than 50mV when load current stepped from 1mA to 500mA,skew time is less than 1μs.