SIM900A 硬件设计手册
目录
目录............................................................................................................................................................................3
版本历史....................................................................................................................................................................7
1 绪论........................................................................................................................................................................8
1.1 相关文档.....................................................................................................................................................8
1.2 术语和解释..................................................................................................................................................9
1.3 安全警告...................................................................................................................................................11
2 SIM900A综述........................................................................................................................................................12
2.1 SIM900A主要特性.....................................................................................................................................12
2.2 SIM900A 功能图.......................................................................................................................................14
2.3 SIM900A 评估板.......................................................................................................................................15
3 应用接口..............................................................................................................................................................16
3.1 SIM900A 引脚描述...................................................................................................................................16
3.2 工作模式....................................................................................................................................................19
3.3 供电............................................................................................................................................................20
3.3.1 供电引脚 ..........................................................................................................................................21
3.3.2 最小功耗 ..........................................................................................................................................21
3.3.3 供电监测 ..........................................................................................................................................21
3.4 开机关机....................................................................................................................................................21
3.4.1 SIM900A开机 ...................................................................................................................................21
3.4.2 SIM900A关机 ...................................................................................................................................24
3.4.3 SIM900A重新启动 ...........................................................................................................................27
3.5 省电............................................................................................................................................................27
3.5.1 最小功能模式 ..................................................................................................................................27
3.5.2 SLEEP模式（慢时钟模式） ...........................................................................................................27
3.5.3 从SLEEP模式唤醒模块 ..................................................................................................................28
3.6 状态转换图（不包含SLEEP模式）.........................................................................................................28
3.7 RTC电源 .....................................................................................................................................................28
3.8 串口............................................................................................................................................................30
3.8.1 串口和调试口功能 ..........................................................................................................................31
3.8.2 软件调试和升级 ..............................................................................................................................32
3.9 音频接口....................................................................................................................................................33
3.9.1 扬声器接口电路...............................................................................................................................34
3.9.2 麦克风接口电路 ..............................................................................................................................35
3.9.3 耳机接口电路 ..................................................................................................................................36
3.9.4 相关电气参数 ..................................................................................................................................36
3.10 SIM卡接口................................................................................................................................................37
3.10.1 SIM应用..........................................................................................................................................37
3.10.2 SIM 卡座的选择............................................................................................................................39
3.11 LCD显示接口...........................................................................................................................................41
SIM900_HD_CN_V1.01 22.02.2010
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