MAX3232串口通信模块

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基于电荷泵的单片机串口通信的热插拔设计

基于电荷泵的单片机串口通信的热插拔设计作者：朱雨蔡坚勇郑华等来源：《电子世界》2013年第17期【摘要】本文采用内部集成了电荷泵模块的MAX3232作为单片机串口通信的热插拔保护电路，该方案能够很好抑制热插拔所引入的尖峰电压，且电路简单，元件较少，以较低的成本获得较好的热插拔性能。

【关键词】热插拔；串口通信；热插拔；MAX32321.引言所谓热插拔，也就是在不切断系统电源的情况下，进行插入或者拔出的操作。

但在正常情况下，对正在工作中设备进行“热插拔”操作是不被允许的，并且“热插拔”的操作会带来许多“副作用”，例如会产生浪涌电流，瞬态电压，静电释放等效应[1][2][3]。

其中浪涌电流效应主要发生在系统的供电模块，而瞬态电压和静电释放效应主要发生在信号端口。

这些效应会导致一些严重后果，例如，单片机不正常复位，单片机端口损坏，一些重要的IC芯片乃至整个电路板烧毁。

但是由于各种原因，例如操作人员疏忽和一些特殊的应用需求，必须保证电路板在热插拔操作的情况下仍然能够正常工作。

因此本文根据单片机串口通信模块需要具备热插拔特殊应用需求，针对热插拔操作所带来的后两种危害设计了相应的保护电路。

2.设计方案比较由于不同设备之间存在电位差的缘故，虽然这些电位差是瞬间的，且电流量并不大，但是在进行热插拔操作时，该电位差通常会超过各种IC芯片的最大耐压值，甚至是IC芯片最大耐压值的几倍从而烧毁IC芯片。

解决瞬态电压的方法就是快速钳制电压。

目前常见的手段包括在电压输入端和地之间使用压敏电阻，TVS（Transient Voltage Suppresser）二极管，也可以使用多层变阻器以及电荷泵电路[3][4]。

如表1所示设计方案的比较。

3.电荷泵的工作原理电荷泵的有许多种分类方法，其中按照内部的结构不同可分为三类：（1）开关式调整器升压泵；（2）无调整电容式电荷泵；（3）可调整电容式电荷泵。

按照输出压降不同，可分为倍圧型和负压型两种。

MAX3232中文资料.pdf

MAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容________________________________________________________________Maxim Integrated Products119-0273; Rev 7; 1/07MegaBaud和UCSP是Maxim Integrated Products, Inc.的商标。

本文是英文数据资料的译文，文中可能存在翻译上的不准确或错误。

如需进一步确认，请在您的设计中参考英文资料。

有关价格、供货及订购信息，请联络Maxim亚洲销售中心：10800 852 1249 (北中国区)，10800 152 1249 (南中国区)，或访问Maxim的中文网站：。

M A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Note 1:V+ and V- can have a maximum magnitude of 7V, but their absolute difference cannot exceed 13V.V CC ...........................................................................-0.3V to +6V V+ (Note 1)...............................................................-0.3V to +7V V- (Note 1)................................................................+0.3V to -7V V+ + V- (Note 1)...................................................................+13V Input VoltagesT_IN, SHDN , EN ...................................................-0.3V to +6V MBAUD...................................................-0.3V to (V CC + 0.3V)R_IN.................................................................................±25V Output VoltagesT_OUT...........................................................................±13.2V R_OUT....................................................-0.3V to (V CC + 0.3V)Short-Circuit DurationT_OUT....................................................................ContinuousContinuous Power Dissipation (T A = +70°C)16-Pin TSSOP (derate 6.7mW/°C above +70°C).............533mW 16-Pin Narrow SO (derate 8.70mW/°C above +70°C)....696mW 16-Pin Wide SO (derate 9.52mW/°C above +70°C)........762mW 16-Pin Plastic DIP (derate 10.53mW/°C above +70°C)...842mW 18-Pin SO (derate 9.52mW/°C above +70°C)..............762mW 18-Pin Plastic DIP (derate 11.11mW/°C above +70°C)..889mW 20-Pin SSOP (derate 7.00mW/°C above +70°C).........559mW 20-Pin TSSOP (derate 8.0mW/°C above +70°C).............640mW 28-Pin TSSOP (derate 8.7mW/°C above +70°C).............696mW 28-Pin SSOP (derate 9.52mW/°C above +70°C).........762mW 28-Pin SO (derate 12.50mW/°C above +70°C).....................1W Operating Temperature RangesMAX32_ _C_ _.....................................................0°C to +70°C MAX32_ _E_ _ .................................................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________3TIMING CHARACTERISTICS—MAX3222/MAX3232/MAX3241(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)ELECTRICAL CHARACTERISTICS (continued)(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容4_______________________________________________________________________________________典型工作特性Ω, T A = +25°C, unless otherwise noted.)LOAD CAPACITANCE (pF)0246810121416182022150MAX3222/MAX3232SLEW RATEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)S L E W R A T E (V /µs )20003000100040005000510152025303540MAX3222/MAX3232SUPPLY CURRENT vs. LOAD CAPACITANCEWHEN TRANSMITTING DATALOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )20003000100040005000TIMING CHARACTERISTICS—MAX3237(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Note 2:MAX3222/MAX3232/MAX3241: C1–C4 = 0.1µF tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF tested at 5.0V ±10%.MAX3237: C1–C4 = 0.1µF tested at 3.3V ±5%; C1–C4 = 0.22µF tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF tested at 5.0V ±10%.Note 3:Transmitter input hysteresis is typically 250mV.MAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________5-7.5-5.0-2.502.55.07.50MAX3241TRANSMITTER OUTPUT VOLTAGEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )2000300010004000500046810121416182022240MAX3241SLEW RATEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)S L E W R A T E (V /µs )20003000100040005000510152025303545400MAX3241SUPPLY CURRENT vs. LOADCAPACITANCE WHEN TRANSMITTING DATALOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )20003000100040005000-7.5-5.0-2.502.55.07.50MAX3237TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE (MBAUD = GND)LOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )200030001000400050000102030504060700MAX3237SLEW RATE vs. LOAD CAPACITANCE(MBAUD = V CC )LOAD CAPACITANCE (pF)S L E W R A T E (V /µs )500100015002000-7.5-5.0-2.502.55.07.50MAX3237TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE (MBAUD = V CC )LOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )5001000150020001020304050600MAX3237SUPPLY CURRENT vs.LOAD CAPACITANCE (MBAUD = GND)LOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )200030001000400050000246810120MAX3237SLEW RATE vs. LOAD CAPACITANCE(MBAUD = GND)LOAD CAPACITANCE (pF)S L E W R A T E (V /µs )2000300010004000500010302040506070MAX3237SKEW vs. LOAD CAPACITANCE(t PLH - t PHL )LOAD CAPACITANCE (pF)1000150050020002500____________________________________________________________________典型工作特性(续)(V CC = +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3k Ω, T A = +25°C, unless otherwise noted.)M A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容6_________________________________________________________________________________________________________________________________________________________________引脚说明MAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________7_______________________________详细说明双电荷泵电压转换器MAX3222/MAX3232/MAX3237/MAX3241的内部电源由两路稳压型电荷泵组成，只要输入电压(V CC )在3.0V至5.5V范围以内，即可提供+5.5V (倍压电荷泵)和-5.5V (反相电荷泵)输出电压。

国产max3232

国产MAX3232简介MAX3232是一款常用的RS232转换芯片，用于在电脑和外部设备之间传递串行数据。

国产MAX3232是国内厂商生产的一种与MAXIM公司生产的MAX3232功能相似的芯片。

国产MAX3232在功能和参数上与MAX3232基本保持一致，但在价格和供货上具有一定优势。

功能特点1.支持RS232标准，实现电平转换。

2.具有高速数据传输能力，通信稳定可靠。

3.低功耗设计，节能环保。

4.集成了保护功能，具有较好的抗干扰能力。

5.独特的设计使其适用于各种工业和通讯场景。

国产MAX3232与进口MAX3232的比较1.价格：国产MAX3232的价格通常比进口MAX3232更为具有竞争力，降低成本。

2.供货周期：国产MAX3232生产商在国内，供货更为便捷，缩短采购周期。

3.技术支持：国产MAX3232的厂商提供本地化的技术支持，解决问题更为便捷。

4.适用性：国产MAX3232根据国内市场的需求进行定制和优化，更适合国内用户需求。

应用场景1.工控设备：国产MAX3232可广泛应用于工控设备中，实现设备之间的稳定通信。

2.通信设备：在通信设备中，国产MAX3232可以帮助设备与中控系统之间实现数据传输。

3.个人DIY项目：爱好者可以利用国产MAX3232进行串口通信的DIY项目，提高通信稳定性。

结论国产MAX3232是一款功能齐全、价格优势明显的RS232转换芯片，可以满足各类通信设备的需求。

国产MAX3232在本地化支持、技术服务等方面具备诸多优势，为用户提供了更好的使用体验。

在未来的发展中，国产MAX3232有望在国内市场越发广泛地应用于各类通信、工控等领域。

MAX3232每次只有在上电后，再连接串口线正常——保护电阻。RS232防雷保护

MAX3232每次只有在上电后，再连接串⼝线正常——保护电阻。

RS232防雷保护原问题：做了块电路板，结果发现，要先对开发板上电, 再打开串⼝超级终端, 串⼝通信才可成功。

但是另外⼀块开发板却没有这个问题。

这⼀般是什么原因造成的？⾃⼰遇到问题：刚焊接好的板⼦，发现串⼝有问题，结果串⼝每次只有在断电上电后需要在上电后重新连接串⼝线才能正常通信原因简述：缺少保护电阻，解决办法：每次断电时拔掉串⼝线下⾯所提到的问题，和上⾯链接中的问题(热插拔才可通信)，其实是同⼀个问题，可能的原因是1. 232收发器芯⽚产⽣电压的那些⼩电容的数值是和数据⼿册上不太⼀致2. 232收发器芯⽚和232插座之间缺少串联保护电阻，或保护电阻数值太⼩。

3. 原来的232收发器芯⽚可能部分失效了如果1和2都已经做到了，将232收发器芯⽚的RXD输⼊管脚和插座RXD之间的串联保护电阻加⼤，⽐如换成1K或10K的，应该就可以了。

如果还不成，就换个232芯⽚吧。

多说⼏句原因吧(以前碰到过该问题所以就研究过)：在不通信的时候，PC串⼝的TXD管脚会输出-5V左右的电压，于是在开发板上的232收发器芯⽚的RXD对应的输⼊管脚(R1IN或R2IN)上维持着-5V左右的电压。

当开发板断电时，232收发器芯⽚的电源管脚没有电压，V+/V-管脚也没有电压，唯独RXD输⼊管脚(R1IN或R2IN)上维持这⼀个-5V左右的电平，不⽤多说就能明⽩这意味着什么。

假如习惯上每次给开发板断电后却让串⼝依旧和 PC保持连接，这意味这232收发器芯⽚长期承受着RXD输⼊管脚-5V但同时⼜让电源管脚和V+/V-为零电平，特别当PC的TXD输出维持这超过-5V甚⾄超过-6V的时候，久⽽久之，这颗芯⽚就会渐渐部分失效或全部失效，于是通信就失败了。

所以换⼀个芯⽚往往就可以解决这个问题。

每次先打开串⼝程序⽽没有通信的时候，-5V或以下的电压就加在TXD管脚上了，如果此时开发板断电但是却接着串⼝，就相当于初始状态是先让232收发器芯⽚处于上述异常的⼯作条件，然后再给开发板上电的时候，就可能出现通信不成功的状况。

MAX3232中文资料_数据手册_参数

万联芯城-电子元器件采购网，提供一站式配套，解决物料烦恼，万联芯城-以良心做好良芯，专为终端工厂企业客户提供电子元器件一站式配套报价服务，客户提交物料清单，商城即可整单报价，整单下单有优惠，万联芯城现货库存销售能够满足多种客户的物料需求，一站式报价为客户节省采购成本，点1MBPS，真正的RS-232收发器使用四个0.1μF外部电容器电源去耦在大多数情况下，一个0.1μF的旁路电容是充足.在对电源敏感的应用中，电源噪声，用电容将V CC 去耦到地与电荷泵电容器C1的值相同.连旁路电容尽可能靠近IC.操作低至2.7V发射机输出将符合EIA / TIA-562的等级 ±3.7V，电源电压低至2.7V.变送器输出时退出关机图3显示了退出时的两个变送器输出关机模式.当它们变得活跃时，显示的分路器输出将与RS-232相反 - （一个发射器输入高，另一个低）.每个发射器都装有3K Ω并联 2500PF的.变送器输出不显示振铃或当它们从停机状态退出时，会产生不希望的瞬变.请注意，变送器仅在使用时才能启用 V-的量值超过大约3V.鼠标可驾驶性 MAX3241专门设计用于供电串口鼠标，同时使用低压电源供电，层数. 它已经通过了领先的鼠标品牌进行了测试制造商如微软和罗技.该 MAX3241成功驱动所有经过测试的串口鼠标满足他们各自的电流和电压要求.图4A显示了发射机输出电压下在3.0V时增加负载电流.图4B显示了一个典型的使用MAX3241连接鼠标.表1. MAX3222 / MAX3237 / MAX3241关闭并启用控制真值表表2.所需的小电容值 5V / DIV V CC = 3.3V C1-C4 = 0.1 μF 2V / DIV T2 50微秒/分 T1图3.退出关机或关机时的变送器输出开机 V CC （V） C1 （μF） 4.5至5.5 0.047 3.0至5.5 0.1 C2，C3，C4 （μF） MAX3222 / MAX3232 / MAX3241 0.33 0.47 1 活性 0 1活性 1小号 SH HD DN ?高-Z 1 0高-Z 0 0 T_OUT ? EN MAX3232典型的操作特性（除非另有说明，否则 V CC = + 3.3V，数据速率为235KBPS，电容为0.1μF，所有发射器负载3KΩ，T A = + 25°C）. -6 -5 -4 -3 -2 -1 0 1 2 3 4五 6 0 MAX3222 / MAX3232发射机输出电压与负载电容负载电容（PF） 2000 3000 1000 4000 5000 V OUT + V OUT - 0 2 4 6 8 10 12 14 16 18 20 22 150 MAX3222 / MAX3232 SLEW RATE与负载电容负载电容（PF） 2000 3000 1000 4000 5000数据速率高达235KBPS + SLEW -SLEW 0五 10 15 20 25三十 35 40 0 MAX3222 / MAX3232电源电流与负载电容传输数据时负载电容（PF） 2000 3000 1000 4000 5000 235KBPS 120KBPS 20KBPS的 R L =3KΩ，C L = 1000PF，一个发射器切换， MBAUD = GND普通手术条件普通手术 NS 200 接收器输出禁用时间 | T PHL - T PLH | ，MBAUD = GND NS 100 0.15 250微秒 0.15接收机传播延迟 NS 200接收器输出使能时间单位 MIN TYP MAX参数时序特性-MAX3237 （V CC = + 3.0V至+ 5.5V，C1-C4 =0.1μF（注2），T A = T MIN 至T MAX ，除非另有说明，典型值为T A = + 25°C.） V CC = 3.0V至4.5V，R L =3KΩ，C L = 250PF，一个发射机切换，MBAUD = V CC 1000 V CC = 4.5V至5 MAX3232详细说明:双电荷泵电压转换器 MAX3222 / MAX3232 / MAX3237 / MAX3241内部电源由一个调节双电荷泵组成提供+ 5.5V的输出电压（倍增电荷泵）和-5.5V（反相电荷泵），无论如何 3.0V至5.5V范围内的输入电压（V CC ）. 该电荷泵工作在不连续模式;如果输出电压小于5.5V，电荷泵启用，如果输出电压超过5.5V，则电荷泵被禁用.每个电荷泵需要一个飞行电容器（C1，C2）和一个储存器电容器（C3，C4）以产生V +和V-电源. RS-232变送器发射机是反相电平转换器， vert CMOS逻辑电平为5.0V EIA / TIA-232级别. MAX3222 / MAX3232 / MAX3241发射机guaran-发球时间为120kbps，差情况下为3k Ωin与1000pF并行，提供与PC-to- PC通讯软件（如 LapLink?）.通常，这三个设备可以以数据速率运行的235kbps.变送器可并联，接收者或小鼠. MAX3222 / MAX3237 / MAX3241的输出级为当设备关闭时，关闭（高阻抗）下模式.当电源关闭时，MAX3222 / MAX3232 / MAX3237 / MAX3241允许输出为驱动高达±12V.发射机输入没有上拉电阻. 将未使用的输入连接到GND或V CC . MAX3237 MegaBaud操作在正常工作模式（MBAUD = GND）下， MAX3237发送器保证250kbps的数据速率差情况下为3k Ω与1000pF并联.这提供了与PC到PC通信的兼容性， Laplink?软件.对于高速串行

单片机与node mcu串口通信的接线方法(一)

单片机与node mcu串口通信的接线方法(一)单片机与NodeMCU串口通信的接线方法介绍在项目开发中，单片机与NodeMCU之间的串口通信是常见的需求。

本文将详细介绍多种串口通信接线方法，包括硬件和软件方面的配置。

硬件接线方法直接连接1.将单片机的TX引脚连接到NodeMCU的RX引脚上。

2.将单片机的RX引脚连接到NodeMCU的TX引脚上。

3.确保单片机和NodeMCU共用一个地线。

使用转接模块1.使用一个串口转接模块，如MAX3232、CP2102等。

2.将单片机的TX引脚连接到转接模块的RX引脚上。

3.将单片机的RX引脚连接到转接模块的TX引脚上。

4.将转接模块的VCC引脚连接到单片机的电源引脚或NodeMCU的5V引脚上。

5.将转接模块的GND引脚连接到单片机的地线或NodeMCU的地线上。

使用逻辑电平转换器1.使用一个逻辑电平转换器模块，如CD4050、74HC4050等。

2.将单片机的TX引脚连接到逻辑电平转换器的输入引脚上。

3.将逻辑电平转换器的输出引脚连接到NodeMCU的RX引脚上。

4.将逻辑电平转换器的VCC引脚连接到单片机的电源引脚或NodeMCU的5V引脚上。

5.将逻辑电平转换器的GND引脚连接到单片机的地线或NodeMCU的地线上。

软件配置方法单片机编程1.在单片机的程序中设置串口通信相关的参数，如波特率、数据位、校验位等。

2.初始化串口，并确保单片机的接收和发送功能都已开启。

3.在主程序中编写发送和接收数据的代码。

NodeMCU编程1.在NodeMCU的程序中引入Serial库。

2.初始化串口，并设置相关的参数，如波特率、数据位、校验位等。

3.在主程序中编写发送和接收数据的代码，使用Serial库提供的函数进行串口通信。

总结本文介绍了单片机与NodeMCU之间串口通信的多种接线方法，包括直接连接、使用转接模块和使用逻辑电平转换器。

同时，也提到了软件配置方面的方法，包括单片机和NodeMCU的编程配置。

低压异步通讯接口电路MAX3232

ＥＡ２２逻辑电平标准。Ｓ３Ｉ一３Ｒ２２接口的逻
将升压电路相关的４只电容容量减少。
ＭＡ３３Ｘ２２主要特点：芯片内部设置
了静电保护电路，可有效抑制高达１ｋ５Ｖ
不：
ＭＡ３３ × ２２各引脚功能描述如表１所
图２ＭＡ２２ＰＸ３３ＥＥ外形图
１０
１１
１２
ＴＮ１Ｉ。第一路ＣＳ１Ｌ逻辑电平输入，来自单片机ＴＤ端。（ＭＯＳＭＯ、一ｒＸＣ、１ｒ＿Ｌ逻辑电平）
ＲＴ。第一路ＣＯＵ１Ｍ０Ｓ１Ｌ逻辑电平输出，单片机ＲＤ端。（ＭＯＳ、＿ｒ去ｘＣ、１ｒ辑电平）＿Ｌ逻
不可同日而语。是Ｒ２２有着广泛的大但Ｓ３
已经不能很好完成这项工作了。 × ２２ＭＡ３３
＿
常见的为１脚ＤＩ封装的 Nhomakorabea ６Ｐ
－
众基础，的技术透明，范简单，易掌是ＭＡ２２的增强品种。能够替代ＭＡ３３ＥＥ它在引脚排列、能等方它规容Ｘ３ ×２２Ｐ。功握。所以目前在对传输速率要求不高的场ＭＡ２２完成５系统与Ｒ２２高电压面也与采用同样封装的ＭＡ２２完全兼Ｘ３ＶＳ３ ×３ｒ．．。。．．１．．．一．．ｌ．。。＿，合，终能保有一席之地。始接口的匹配，同时也能实现３Ｖ低压系统容，以代换。代换时在外围电路方面，可需Ｒ２２最基本的通讯方式为数据接与Ｒ２２接口的互联。Ｓ３Ｓ３收及数据传送双线传输这种模式。它采用

MAX3232电平转换原理图

RS232TO TTL 通讯模块
实现RS232到TTL数据转换。

芯片采用MAX3232适用电压3V-5.5V,具有ESD保护功能、支持流控制、零延时自动收发转换和波特率自适应特点，即插即用，稳定可靠。

主要资源：
一、DB9母头RS232接口带流控功能可直接接电脑
二、2.54排针RS232接口带流控功能可替代DB9接头
三、3个指示灯分别是电源指示灯、数据收指示灯、数据发指示灯
四、2.54排针TTL接口带流控功能可直接接TTL设备
淘宝网站
https:///?spm=2013.1.1000126.d21.lOnOC1
以MCU单片机TTL到PC台式机RS232数据通信为例
1、PC台式机接DB9接口
2、MCU通过杜邦线接排针P1接口
P1接口说明
1GND接GND信号流向：GND
2VCC接3V-5V信号流向：VCC<--MCU_5V/MCU_3.3V
3RX接MCU_TX信号流向：PC_RX<--MAX3232<--RX
4TX接MCU_RX信号流向：PC_TX-->MAX3232-->TX
5CTS接MCU_RTS信号流向：PC_CTS<--MAX3232<--MCU_RTS 6RTS接MCU_CTS信号流向：PC_RTS-->MAX3232-->MCU_CTS
产品附件
1、RS232-TTL小板一个
2、杜邦线十根十种颜色
3、防静电自封袋一个
4、原理图
淘宝
https:///?spm=2013.1.1000126.d21.lOnOC1产品图片。

MAX3232中文资料

本文是英文数据资料的译文，文中可能存在翻译上的不准确或错误。

如需进一步确认，请在您的设计中参考英文资料。

有关价格、供货及订购信息，请联络Maxim亚洲销售中心：10800 852 1249 (北中国区)，10800 152 1249 (南中国区)，或访问Maxim的中文网站：。

M A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容2_______________________________________________________________________________________ABSOLUTE MAXIMUM RATINGSELECTRICAL CHARACTERISTICS(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.Note 1:V+ and V- can have a maximum magnitude of 7V, but their absolute difference cannot exceed 13V.V CC ...........................................................................-0.3V to +6V V+ (Note 1)...............................................................-0.3V to +7V V- (Note 1)................................................................+0.3V to -7V V+ + V- (Note 1)...................................................................+13V Input VoltagesT_IN, SHDN , EN ...................................................-0.3V to +6V MBAUD...................................................-0.3V to (V CC + 0.3V)R_IN.................................................................................±25V Output VoltagesT_OUT...........................................................................±13.2V R_OUT....................................................-0.3V to (V CC + 0.3V)Short-Circuit DurationT_OUT....................................................................ContinuousContinuous Power Dissipation (T A = +70°C)16-Pin TSSOP (derate 6.7mW/°C above +70°C).............533mW 16-Pin Narrow SO (derate 8.70mW/°C above +70°C)....696mW 16-Pin Wide SO (derate 9.52mW/°C above +70°C)........762mW 16-Pin Plastic DIP (derate 10.53mW/°C above +70°C)...842mW 18-Pin SO (derate 9.52mW/°C above +70°C)..............762mW 18-Pin Plastic DIP (derate 11.11mW/°C above +70°C)..889mW 20-Pin SSOP (derate 7.00mW/°C above +70°C).........559mW 20-Pin TSSOP (derate 8.0mW/°C above +70°C).............640mW 28-Pin TSSOP (derate 8.7mW/°C above +70°C).............696mW 28-Pin SSOP (derate 9.52mW/°C above +70°C).........762mW 28-Pin SO (derate 12.50mW/°C above +70°C).....................1W Operating Temperature RangesMAX32_ _C_ _.....................................................0°C to +70°C MAX32_ _E_ _ .................................................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°CMAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________3TIMING CHARACTERISTICS—MAX3222/MAX3232/MAX3241(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)ELECTRICAL CHARACTERISTICS (continued)(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)M A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容4________________________________________________________________________________________________________________________________________________________________典型工作特性(V CC = +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3k Ω, T A = +25°C, unless otherwise noted.)-6-5-4-3-2-101234560MAX3222/MAX3232TRANSMITTER OUTPUT VOLTAGEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )20003000100040005000246810121416182022150MAX3222/MAX3232SLEW RATEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)S L E W R A T E (V /µs )20003000100040005000510152025303540MAX3222/MAX3232SUPPLY CURRENT vs. LOAD CAPACITANCEWHEN TRANSMITTING DATALOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )20003000100040005000TIMING CHARACTERISTICS—MAX3237(V CC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)Note 2:MAX3222/MAX3232/MAX3241: C1–C4 = 0.1µF tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF tested at 5.0V ±10%.MAX3237: C1–C4 = 0.1µF tested at 3.3V ±5%; C1–C4 = 0.22µF tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF tested at 5.0V ±10%.Note 3:Transmitter input hysteresis is typically 250mV.MAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________5-7.5-5.0-2.502.55.07.50MAX3241TRANSMITTER OUTPUT VOLTAGEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )2000300010004000500046810121416182022240MAX3241SLEW RATEvs. LOAD CAPACITANCELOAD CAPACITANCE (pF)S L E W R A T E (V /µs )20003000100040005000510152025303545400MAX3241SUPPLY CURRENT vs. LOADCAPACITANCE WHEN TRANSMITTING DATALOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )20003000100040005000-7.5-5.0-2.502.55.07.50MAX3237TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE (MBAUD = GND)LOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )200030001000400050000102030504060700MAX3237SLEW RATE vs. LOAD CAPACITANCE(MBAUD = V CC )LOAD CAPACITANCE (pF)S L E W R A T E (V /µs )500100015002000-7.5-5.0-2.502.55.07.50MAX3237TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE (MBAUD = V CC )LOAD CAPACITANCE (pF)T R A N S M I T T E R O U T P U T V O L T A G E (V )5001000150020001020304050600MAX3237SUPPLY CURRENT vs.LOAD CAPACITANCE (MBAUD = GND)LOAD CAPACITANCE (pF)S U P P L Y C U R R E N T (m A )200030001000400050000246810120MAX3237SLEW RATE vs. LOAD CAPACITANCE(MBAUD = GND)LOAD CAPACITANCE (pF)S L E W R A T E (V /µs )2000300010004000500010302040506070MAX3237SKEW vs. LOAD CAPACITANCE(t PLH - t PHL )LOAD CAPACITANCE (pF)1000150050020002500____________________________________________________________________典型工作特性(续)(V CC = +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3k Ω, T A = +25°C, unless otherwise noted.)M A X 3222/M A X 3232/M A X 3237/M A X 32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容6_________________________________________________________________________________________________________________________________________________________________引脚说明MAX3222/MAX3232/MAX3237/MAX32413.0V至5.5V、低功耗、1Mbps、真RS-232收发器，使用四只0.1µF外部电容_______________________________________________________________________________________7_______________________________详细说明双电荷泵电压转换器MAX3222/MAX3232/MAX3237/MAX3241的内部电源由两路稳压型电荷泵组成，只要输入电压(V CC )在3.0V至5.5V范围以内，即可提供+5.5V (倍压电荷泵)和-5.5V (反相电荷泵)输出电压。

max3232工作原理

max3232工作原理
MAX3232是一款集成电路，工作原理如下：
1. RS-232转换：MAX3232主要用于将RS-232标准电平转换为适合微控制器或其他低压逻辑电平的电平。

RS-232电平通常为正负12V，而微控制器或其他逻辑电路的工作电平通常为0V和3.3V或5V。

MAX3232通过内部电压调节器和双向电平转换电路实现将RS-232电平转换为适合逻辑电路的电平。

2. 电平转换：MAX3232内部有电平转换电路，能够将RS-232接收和发送的电平转换为适合逻辑电路的电平。

当RS-232接收信号为高电平时，MAX3232将其转换为逻辑电路所能接受的高电平信号。

当RS-232接收信号为低电平时，MAX3232
将其转换为逻辑电路所能接受的低电平信号。

3. 信号调整：MAX3232还能调整RS-232信号的电平幅度。

RS-232标准定义了标准电平和标准电平范围。

不同设备可能对电平范围有不同的要求。

MAX3232内部的电平调整电路可以根据需求调整出适合各种设备的信号电平。

总的来说，MAX3232的工作原理是通过将RS-232标准电平转换为适合逻辑电路的电平，并调整信号的电平幅度，实现RS-232与微控制器或其他逻辑电路的连接。

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PACKAGING INFORMATIONOrderable Device Status(1)PackageType PackageDrawingPins PackageQtyEco Plan(2)Lead/Ball Finish MSL Peak Temp(3)MAX3232CD ACTIVE SOIC D1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDB ACTIVE SSOP DB1680Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDBE4ACTIVE SSOP DB1680Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDBR ACTIVE SSOP DB162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDBRE4ACTIVE SSOP DB162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDE4ACTIVE SOIC D1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDR ACTIVE SOIC D162500Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDRE4ACTIVE SOIC D162500Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDW ACTIVE SOIC DW1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDWG4ACTIVE SOIC DW1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDWR ACTIVE SOIC DW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CDWRG4ACTIVE SOIC DW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPW ACTIVE TSSOP PW1690Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPWE4ACTIVE TSSOP PW1690Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPWG4ACTIVE TSSOP PW1690Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPWR ACTIVE TSSOP PW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPWRE4ACTIVE TSSOP PW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232CPWRG4ACTIVE TSSOP PW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232ID ACTIVE SOIC D1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDB ACTIVE SSOP DB1680Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDBE4ACTIVE SSOP DB1680Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDBR ACTIVE SSOP DB162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDBRE4ACTIVE SSOP DB162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDE4ACTIVE SOIC D1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDR ACTIVE SOIC D162500Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMOrderable Device Status(1)PackageType PackageDrawingPins PackageQtyEco Plan(2)Lead/Ball Finish MSL Peak Temp(3)MAX3232IDRE4ACTIVE SOIC D162500Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDW ACTIVE SOIC DW1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDWE4ACTIVE SOIC DW1640Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDWR ACTIVE SOIC DW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IDWRE4ACTIVE SOIC DW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IPW ACTIVE TSSOP PW1690Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IPWE4ACTIVE TSSOP PW1690Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IPWR ACTIVE TSSOP PW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIMMAX3232IPWRE4ACTIVE TSSOP PW162000Green(RoHS&no Sb/Br)CU NIPDAU Level-1-260C-UNLIM(1)The marketing status values are defined as follows:ACTIVE:Product device recommended for new designs.LIFEBUY:TI has announced that the device will be discontinued,and a lifetime-buy period is in effect.NRND:Not recommended for new designs.Device is in production to support existing customers,but TI does not recommend using this part in a new design.PREVIEW:Device has been announced but is not in production.Samples may or may not be available.OBSOLETE:TI has discontinued the production of the device.(2)Eco Plan-The planned eco-friendly classification:Pb-Free(RoHS),Pb-Free(RoHS Exempt),or Green(RoHS&no Sb/Br)-please check /productcontent for the latest availability information and additional product content details.TBD:The Pb-Free/Green conversion plan has not been defined.Pb-Free(RoHS):TI's terms"Lead-Free"or"Pb-Free"mean semiconductor products that are compatible with the current RoHS requirements for all6substances,including the requirement that lead not exceed0.1%by weight in homogeneous materials.Where designed to be soldered at high temperatures,TI Pb-Free products are suitable for use in specified lead-free processes.Pb-Free(RoHS Exempt):This component has a RoHS exemption for either1)lead-based flip-chip solder bumps used between the die and package,or2)lead-based die adhesive used between the die and leadframe.The component is otherwise considered Pb-Free(RoHS compatible)as defined above.Green(RoHS&no Sb/Br):TI defines"Green"to mean Pb-Free(RoHS compatible),and free of Bromine(Br)and Antimony(Sb)based flame retardants(Br or Sb do not exceed0.1%by weight in homogeneous material)(3)MSL,Peak Temp.--The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications,and peak solder temperature.Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided.TI bases its knowledge and belief on information provided by third parties,and makes no representation or warranty as to the accuracy of 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