a 
 
 
 
 
硬件设计手册 
SIM900A_HD_CN_V1.01
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
SIM900A  硬件设计手册                                                                                                                                                     
 
 
文档名称:  SIM900A 硬件设计手册 
版本:  1.01 
日期:  2010-02-22 
状态:  发布 
文档控制号:  SIM900A_HD_CN_V1.01 
 
前言 
 
 
感谢您使用 SIMCom 有限公司提供的 SIM900A 模块。本产品具有标准 AT 命令接口,可以提供 GSM 语
音、短消息等业务。使用前请务必仔细阅读此用户手册,您将领略其完善强大的功能和简洁的操作方法。   
本设备主要用于语音或者数据通信,本公司不承担由于客户不正常操作造成的财产或者人身伤害责任。
请客户按照手册中的技术规格和参考设计开发相应的产品。同时注意使用移动产品特别是 GSM 产品应该
关注的一般安全事项。   
在未声明之前,本公司有权根据技术发展的需要对本手册内容进行更改   
 
 
 
本手册版权属于SIMCom有限公司,任何人未经我公司书面同意复制将承担法律责任。 
版权声明 
 
 
SIM900_HD_CN_V1.01                                                                                                                                                          22.02.2010
 
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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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SIM900A  硬件设计手册                                                                                                                                                     
 
3.12  键盘接口..................................................................................................................................................41 
3.13 模数转换器(ADC) ..............................................................................................................................42 
3.14 RI信号线动作...........................................................................................................................................43 
3.15  网络状态指示灯......................................................................................................................................44 
3.16  通用输入输出(GPIO)..............................................................................................................................44 
3.17  外部复位输入..........................................................................................................................................45 
3.18 PWM .........................................................................................................................................................45 
3.19 I2C总线.....................................................................................................................................................46 
4  天线接口..............................................................................................................................................................46 
4.1  模块射频输出功率....................................................................................................................................46 
4.2  模射频接收灵敏度....................................................................................................................................47 
4.3  模块工作频段............................................................................................................................................47 
5  电气,可靠性和射频特性..................................................................................................................................47 
5.1  绝对最大值................................................................................................................................................47 
5.2  工作温度....................................................................................................................................................47 
5.3  电源额定值................................................................................................................................................48 
5.4  耗流............................................................................................................................................................49 
5.5  静电放电....................................................................................................................................................49 
6  机械尺寸..............................................................................................................................................................50 
6.1 SIM900A的机械尺寸.................................................................................................................................50 
6.2 SIM900A的顶视图和底视图.....................................................................................................................52 
6.3 SIM900A引脚分配.....................................................................................................................................53 
6.4 SIM900A推荐焊接炉温曲线图.................................................................................................................55 
 
 
 
 
 
 
 
 
 
SIM900_HD_CN_V1.01                                                                                                                                                          22.02.2010
 
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SIM900A  硬件设计手册                                                                                                                                                     
 
表格索引 
表 1: 相关文档 ................................................................................................................................................................ 8 
表 2: 术语和解释 ............................................................................................................................................................ 9 
表 3: SIM900A主要特性 ................................................................................................................................................ 12 
表 4:编码格式和耦合时最大网络数据速度率 .......................................................................................................... 14 
表 5:引脚描述 .............................................................................................................................................................. 16 
表  6:  工作模式............................................................................................................................................................... 19 
表  7:串口引脚定义 ...................................................................................................................................................... 30 
表  8:  串口的逻辑电平................................................................................................................................................... 31 
表  9:音频接口引脚定义 .............................................................................................................................................. 33 
表  10:音频输入参数 .................................................................................................................................................... 36 
图  11:音频输出参数 .................................................................................................................................................... 37 
表  12:SIM卡接口引脚定义 ......................................................................................................................................... 37 
表  13:  引脚描述(AMPHENOL SIM卡座) .................................................................................................................... 39 
表  14:引脚描述  (MOLEX SIM卡座) ......................................................................................................................... 40 
表  15:LCD接口引脚定义 ............................................................................................................................................ 41 
表  16:键盘接口引脚信号定义 .................................................................................................................................... 41 
表  17:ADC参数............................................................................................................................................................ 43 
表  18:RI信号线动作 .................................................................................................................................................... 43 
表  19:NETLIGHT工作状态 ........................................................................................................................................ 44 
表  20:GPIO接口引脚定义........................................................................................................................................... 45 
表  21:PWM引脚定义................................................................................................................................................... 45 
表  22:I2C总线接口信号定义 ...................................................................................................................................... 46 
表  23: SIM900A  传导射频输出功率 ............................................................................................................................ 46 
表  24: SIM900A  传导射频接收灵敏度 ........................................................................................................................ 47 
表  25: SIM900A  工作频段 ............................................................................................................................................ 47 
表  26:绝对最大值 ........................................................................................................................................................ 47 
表  27:SIM900A工作温度 ............................................................................................................................................ 47 
表  28:SIM900A电源额度值 ........................................................................................................................................ 48 
表  29: SIM900A耗流...................................................................................................................................................... 49 
表  30:ESD  性能参数(温度:25℃,湿度:45%)................................................................................................ 49 
表  31:引脚分配 ............................................................................................................................................................ 53 
 
 
 
 
 
 
 
 
SIM900_HD_CN_V1.01                                                                                                                                                          22.02.2010
 
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SIM900A  硬件设计手册                                                                                                                                                     
 
图片索引 
图  1:SIM900A  功能框图 ............................................................................................................................................ 14 
图  2:SIM900A评估板顶视图 ...................................................................................................................................... 15 
图  3:VBAT  输入参考电路.......................................................................................................................................... 20 
图  4:供电输入参考设计电路 ...................................................................................................................................... 20 
图  5:猝发时VBAT的跌落............................................................................................................................................ 21 
图  6:SIM900A使用驱动电路开机 .............................................................................................................................. 22 
图  7:SIM900A使用按键开机 ...................................................................................................................................... 22 
图  8:使用PWRKEY开机时序图 ................................................................................................................................. 23 
图  9:SIM900A使用驱动电路开机 .............................................................................................................................. 23 
图  10:SIM900A使用按键开机 .................................................................................................................................... 24 
图  11:使用PWRKEY  和PWRKEY_OUT  开机时序图............................................................................................. 24 
图  12:使用PWRKEY引脚关机时序图........................................................................................................................ 25 
图  13:使用PWRKEY和PWRKEY_OUT关机时序图................................................................................................. 25 
图  14:系统重启时序图 ................................................................................................................................................ 27 
图  15:状态转换图 ........................................................................................................................................................ 28 
图  16:RTC采用不可充电电池供电............................................................................................................................. 29 
图  17:RTC采用可充电电池供电................................................................................................................................. 29 
图  18:RTC采用电容供电............................................................................................................................................. 29 
图  19:SEIKO XH414H-IV01E  充电特性................................................................................................................... 30 
图  20:串口连接图 ........................................................................................................................................................ 31 
图  21:软件升级和调试接口 ........................................................................................................................................ 33 
图  22:RS232 电平转换电路 ........................................................................................................................................ 33 
图  23:扬声器接口电路 ................................................................................................................................................ 34 
图  24:带音频放大器的音频接口电路 ........................................................................................................................ 35 
图  25:麦克风接口电路 ................................................................................................................................................ 35 
图  26:耳机接口电路 .................................................................................................................................................... 36 
图  27:8 引脚卡座的接口推荐电路 ............................................................................................................................. 38 
图  28:6 引脚卡座的接口推荐电路 ............................................................................................................................. 38 
图  29:AMPHENOL C707 10M006 512 2 SIM卡座尺寸图 ........................................................................................ 39 
图  30:MOLEX 91228 SIM卡座................................................................................................................................... 40 
图  31:键盘接口参考电路 ............................................................................................................................................ 42 
图  32:ADC结构图........................................................................................................................................................ 42 
图 33:SIM900A作为被叫 ............................................................................................................................................. 43 
图  34:SIM900A作为主叫 ............................................................................................................................................ 44 
图  35:NETLIGHT参考设计电路................................................................................................................................. 44 
图  36:复位时序图 ........................................................................................................................................................ 45 
图  37:模块顶视图和侧视图的物理尺寸(单位:MM) ......................................................................................... 50 
图  38:模块底视图的物理尺寸(单位:MM) ......................................................................................................... 51 
图  39:推荐PCB封装图(单位:MM)...................................................................................................................... 51 
图  40:SIM900A顶视和底视图 .................................................................................................................................... 52 
图  41:SIM900A引脚图(顶视图) ............................................................................................................................ 53 
图  42:SIM900A推荐焊接炉温曲线图 ........................................................................................................................ 55 
SIM900_HD_CN_V1.01                                                                                                                                                          22.02.2010
 
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  SIM900A  硬件设计手册                                                                                                                                                   
 
版本历史 
日期 
2010-02-22 
 
 
版本 
1.01 
 
 
变更描述 
初版 
 
 
作者 
李刚 
 
 
SIM900_HD_V1.01                                                          7                                                                                                     22.02.2010  
SIM900A  硬件设计手册                                                                                                                                                     
 
1 绪论 
本文档描述了SIM900A的硬件应用接口,包括相关应用场合的电路连接以及射频接口等。SIM900A的
应用十分广泛,本文档将详细介绍SIM900A的所有功能。 
本文档可以帮助用户快速的了解SIM900A的接口定义、电器性能和结构尺寸的详细信息。结合本文档
和其他的SIM900A的应用文档,用户可以快速的使用SIM900A来设计移动应用方案。 
1.1 相关文档 
表 1: 相关文档 
序号  文档名称 
[1] 
SIM900_ATC 
注释 
SIM900_ATC 
Serial asynchronous automatic dialing and control 
Digital  cellular  telecommunications  (Phase  2+);  AT  command  set  for  GSM 
Mobile Equipment (ME) 
Support GSM 07.10 multiplexing protocol   
Digital  cellular  telecommunications  (Phase  2+);  Use  of  Data  Terminal 
Equipment  –  Data  Circuit  terminating  Equipment  (DTE  –  DCE)  interface  for 
Short Message Service (SMS) and Cell Broadcast Service (CBS) 
Digital cellular telecommunications system (Phase 2+); Specification of the SIM 
Application  Toolkit  for  the  Subscriber  Identity  Module  –  Mobile  Equipment 
(SIM – ME) interface 
Digital  cellular  telecommunications  system  (Phase  2+);  Specification  of  the 
Subscriber Identity Module – Mobile Equipment (SIM – ME) interface 
Digital  cellular 
language-specific information 
Digital cellular telecommunications system (Phase 2);    Mobile Station (MS) 
conformance specification;  Part 1: Conformance specification 
AN_Serial Port 
telecommunications  system  (Phase  2+);  Alphabets  and 
[2] 
[3] 
[4] 
[5] 
ITU-T  Draft  new 
recommendation 
V.25ter: 
GSM 07.07: 
GSM 07.10: 
GSM 07.05: 
[6] 
GSM 11.14: 
[7] 
GSM 11.11: 
[8] 
GSM 03.38: 
[9] 
GSM 11.10 
[10] 
AN_Serial Port 
 
 
SIM900_HD_CN_V1.01                                                                                                                                                          22.02.2010
 
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