The RT9818 is a micro-power voltage detectorsupervising the power supply voltage level formicroprocessors (μP) or digital systems. It providesinternally fixed threshold levels with 0.1V per step rangingfrom 1.2V to 5V, which covers most digital applications. Itfeatures low supply current of 3μA. The RT9818 performssupervisory function by sending out a reset signalwhenever the VDD voltage falls below a preset thresholdlevel. This reset signal will last the whole period beforeVDD recovering. Once VDD recovered upcrossing thethreshold level, the reset signal will be released after acertain delay time. RT9818 is provided in SC-82, SC-70-3,SOT-23-3, SOT-23-5 and SOT-89 packages.