Abstract: A high-accuracy,low-dropout (LDO) voltage regulator is presented.Using the slow-rolloff frequency compensation scheme,the LDO effectively overcomes the stability problem,facilitates the use of a ceramic capacitor,and improves the output voltage accuracy,which is critical for powering high-performance analog circuitry.The slow-rolloff compensation scheme is realized by introducing three pole-zero pairs,including the proposed pole-zero pair and sense zero.The post-layout simulation results demonstrate that this LDO has robust system stability,a high open-loop gain,and a high unit-gain frequency,which lead to excellent regulation and transient response performance.The line and load regulation are 27μV/V and 3.78μV/mA,and the overshoots of the output voltage are less than 30mV,while the dropout voltage is 120mV for a 150mA load current.

Key words: voltage regulator, LDO, slow-rolloff frequency compensation, line regulation, load regulation