A low-dropout regulator comprises a high-gain error amplifier having a
differential input stage and a single-ended output, a high-swing
high-positive-gain second stage with input connecting to the output of
the error amplifier and a single-ended output, a p-type MOS transistor
with gate terminal connecting to the output of the second stage, source
terminal connecting to the supply voltage, and drain terminal to the
output of the low-dropout regulator. A first-order high-pass feedback
network connects the output of the low-dropout regulator and the positive
input of the error amplifier, and a damping-factor-control means
comprising a negative gain stage with a feedback capacitor connects the
input and output of this gain stage. A capacitor is connected between the
output of the error amplifier and the output of the low-dropout
regulator, while a voltage reference connects to the negative input of
the error amplifier. The regulator does not require an off-chip capacitor
for stability and has improved load transient response and power supply
rejection ratio.