双电源电压SIM卡

摘要：标准的GSM手机用户识别模块（SIM卡），使无线服务供应商识别用户和计费信息。虽然大多数SIM卡改变至3V操作，本应用笔记介绍了如何适应在过渡期间的5V。

Maxim>Designsupport>Appnotes>BatteryManagement>APP1763Maxim>Designsupport>Appnotes>Power-SupplyCircuits>APP1763Keywords:sim,SIMcard,powersupply,MOSFET,mosfet,dcdc,dc-dc,wirelessJun19,2000APPLICATIONNOTE1763Dual-VoltageSupplyPowersSIMCardGlobal-system-for-mobile-communicationphoneshaveasubscriber-identificationmodule(SIM)thatallowslocalwirelessproviderstorecognizetheuserandhisorherbillinginformation.AlthoughmostSIMsarechangingto3Voperation,theyalsoaccommodate5Vaswellduringthetransition.IC1inFigure1combinesastep-updc/dcconverterwithalinearregulator,allowingittoregulat