RT9818 Micro-Power Voltage Detectors General Description Features zz z zz Internally Fixed Threshold 1.2V to 5V in 0.1V Step The RT9818 is a micro-power voltage detector supervising zz z zz High Accuracy 1.5% the power supply voltage level for microprocessors (P) zz z zz Low Supply Current 3A or digital systems. It provides internally fixed threshold zz z zz No External Components Required levels with 0.1V per step ranging from 1.2V to 5V, which zz z zz Quick Reset within 20s covers most digital applications. It features low supply zz z zz Built-in Recovery Delay Include 0ms, 55ms, 220ms, current of 3A. The RT9818 performs supervisory function 450ms Options by sending out a reset signal whenever the V voltage DD zz z zz Low Functional Supply Voltage 0.9V falls below a preset threshold level. This reset signal will zz z zz N-Channel Open-Drain Output last the whole period before V recovering. Once V DD DD zz z zz Small SC-82, SC-70-3, SOT-23-3, SOT-23-5, SOT-89 recovered upcrossing the threshold level, the reset signal Packages will be released after a certain delay time. RT9818 is zz z zz RoHS Compliant and 100% Lead (Pb)-Free provided in SC-82, SC-70-3, SOT-23-3, SOT-23-5 and SOT-89 packages. Applications Ordering Information z Computers - RT9818 z Controllers Package Type z Intelligent Instruments U3 : SC-70-3 z Critical P and C Power Monitoring V : SOT-23-3 VL : SOT-23-3 (L-Type) z Portable/Battery-Powered Equipment B : SOT-23-5 X : SOT-89 Marking Information Y : SC-82 YR : SC-82 (R-Type) For marking information, contact our sales representative Lead Plating System directly or through a Richtek distributor located in your P : Pb Free G : Green (Halogen Free and Pb Free) area. Threshold Voltage 12 : 1.2V 13 : 1.3V Typical Application Circuit : 49 : 4.9V 50 : 5.0V Reset Active Timeout Period 100k RT9818 A = 0ms (RESET) Pull Up GND B = 55ms (RESET) VDD VDD C = 220ms (RESET) P D = 450ms (RESET) RESET/ RESET/ E = 0ms (RESET) RESET RESET F = 55ms (RESET) G = 220ms (RESET) H = 450ms (RESET) Note : Richtek products are : RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS9818-10 May 2013 www.richtek.com 1RT9818 Pin Configurations (TOP VIEW) VDD GND NC RESET/ RESET NC 3 4 3 4 3 2 2 2 VDD RESET/ GND RESET/ VDD RESET GND RESET SC-82 SC-82 (R-Type) SC-70-3 NC NC VDD VDD 5 4 3 3 1 23 23 2 2 VDD GND GND GND RESET/ RESET/ RESET/ VDD GND RESET/ RESET RESET RESET RESET SOT-23-3 SOT-23-3 (L-Type) SOT-23-5 SOT-89 Functional Pin Description Pin Name Pin Function GND Ground RESET Active Low Open-Drain Reset Output RESET Active High Open-Drain Reset Output VDD Power Pin Function Block Diagram VDD RESET/ RESET Timer CMP N MOS VSET GND Threshold Voltage Setting POR Power On Reset Timing Diagram V DD V TH 0V V RESET Delay Time (0, 55, 220, 450ms) 0V V RESET Delay Time (0, 55, 220, 450ms) 0V Copyright 2013 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS9818-10 May 2013 2