A 10 nA Ultra-Low Quiescent Current and 60 ns Fast Transient Response Low-Dropout Regulator for Internet-of-Things

Ultra-low quiescent current (
$I_{Q}$
) low-dropout regulator is the only solution for compact size Internet of Things (IoT) electronic devices. This paper presents an ultra-low
$I_{Q}$
low dropout regulator, including low
$I_{Q}$
error amplifier (EA) compensated by the adaptive current control (ACC), low leakage feedback network, low
$I_{Q}$
current comparator, analog transient enhancement (ATE), and digital transient enhancement (DTE). The chip was fabricated in a standard
$0.5~\mu \text{m}$
CMOS process. Measurement results show the current peak efficiency of the LDO is as high as 99.99%. Besides, owing to ATE and DTE circuits, when the load current changes from 1mA to 50mA with a 10 ns edge time, the measured undershoot and overshoot voltages are 75 mV and 50 mV, respectively, with the recovery time (
$T_{R}$
) of 60 ns and 80 ns, respectively, where the best 0.003 ps FoM is achieved.