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 > Design support > App notes > Battery Management > APP 1763 Maxim > Design support > App notes > Power-Supply Circuits > APP 1763 Keywords: sim, SIM card, power supply, MOSFET, mosfet, dcdc, dc-dc, wireless Jun 19, 2000 APPLICATION NOTE 1763 Dual-Voltage Supply Powers SIM Card Global-system-for-mobile-communication phones have a subscriber-identification module (SIM) that allows local wireless providers to recognize the user and his or her billing information. Although most SIMs are changing to 3V operation, they also accommodate 5V as well during the transition. IC1 in Figure 1 combines a step-up dc/dc converter with a linear regulator, allowing it to regulat……