MAX232DW - 120kbps Dual RS-232 Transceiver | Texas Instruments
料号： MAX232DW ✓ 量产中MAX232DW 概述
An RS-232 transceiver is an interface IC that bridges a digital logic system and a serial communications port using the voltage-defined RS-232 standard. The MAX232 belongs to the RS-232 transceiver hierarchy, where a line driver converts TTL/CMOS inputs into bipolar RS-232 outputs and a line receiver converts bipolar inputs into TTL/CMOS levels. This allows equipment with a 5 V UART or microprocessor interface to communicate with legacy RS-232 ports without implementing discrete level-shifting networks.
Key features include two transmit channels, two receive channels, operation to 120 kbit/s, a typical 8 mA supply current, receiver input capability of ±30 V, and compatibility with TIA/EIA-232-F and ITU Recommendation V.28. The receiver has a typical transition threshold of 1.3 V and typical hysteresis of 0.5 V. These characteristics provide noise margin and stable interpretation of the bipolar RS-232 signal while retaining the familiar ±9 V driver levels.
The device combines four RS-232 signal-conditioning channels with an on-chip charge-pump voltage generator. Charge-pump capacitors connected to the designated voltage-generator pins create the positive and negative supply levels needed by the drivers. This architecture eliminates the negative power supply otherwise required by many discrete RS-232 implementations, while the receiver side provides the electrical translation needed to protect and interface a 5 V logic device.
Typical uses include industrial serial consoles, point-of-sale equipment, data-acquisition systems, test and measurement instruments, service interfaces, and legacy peripheral connections. A microcontroller can connect its UART TX and RX signals to the appropriate driver and receiver channels, while the external RS-232 connector receives the bipolar line outputs. The 120 kbit/s capability covers many legacy control and communications protocols without requiring a high-speed RS-485 interface.
The principal design consideration is the charge-pump capacitor network and RS-232 connector routing. Capacitors must be connected exactly as required by the manufacturer datasheet, and external line protection should be evaluated for the target cable length and environment. Logic levels and signal polarity must also be checked at each UART channel because the MAX232 provides level conversion, not automatic inversion or protocol handling.
This product page consolidates the verified manufacturer specifications, distributor availability, cross-reference information, and engineering guidance for MAX232DW. It also distinguishes a genuine same-package replacement from devices with different charge-pump capacitor requirements or package dimensions, helping engineers avoid substitutions that require PCB or component changes.
直接替换替代料： MAX232DW ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
MAX232IDWR
✅ 直接替换📋 参考替代料（不在目录中）
MAX232EIDR
✅ 直接替换📋 参考替代料（不在目录中）
MAX232EIDWG4
✅ 直接替换📋 参考替代料（不在目录中）
MAX232ECWE
✅ 直接替换📋 参考替代料（不在目录中）
MAX232AEUE+
✅ 直接替换📋 参考替代料（不在目录中）
MAX232DW 规格参数
| Product Type | Dual RS-232 driver/receiver with capacitive voltage generator |
| Number of Drivers | 2 |
| Number of Receivers | 2 |
| 数据速率 | 120 kbit/s |
| Nominal Supply Voltage | 5 V |
| Supply Voltage Range | 4.5 V to 5.5 V |
| RS-232 Driver Output Level | Approximately ±9 V |
| Receiver Input Voltage Range | ±30 V |
| ESD Protection | ±2 kV |
| Receiver Transition Threshold | 1.3 V typical |
| Receiver Hysteresis | 0.5 V typical |
| 电源电流 | 8 mA typical |
| 封装 | 16-pin SOIC |
| 安装类型 | Surface mount |
| Interface Standard | TIA/EIA-232-F and ITU Recommendation V.28 |
| Logic Compatibility | 5 V TTL/CMOS |
MAX232DW 16-pin soic 引脚配置指南
MAX232DW（16-pin soic 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： MAX232DW.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MAX232DW 适用于 6 应用s: Microcontroller UART to RS-232 Interface, Industrial Serial Console, Point-of-Sale and Peripheral Connectivity, Data-Acquisition and Test Equipment, Legacy Service and Configuration Port, Instrumentation and Control Panel.
Microcontroller UART to RS-232 Interface
The MAX232DW is suitable for connecting a 5 V microcontroller UART to a legacy RS-232 port because it converts two TTL/CMOS logic channels into two bipolar RS-232 driver outputs and converts two receiver inputs back to 5 V logic. Its verified 120 kbit/s rate covers common serial-control protocols, while the single 5 V supply removes the need for a separate negative rail. The on-chip capacitive voltage generator produces approximately ±9 V output levels internally. Design the board with the manufacturer-specified charge-pump capacitors, local supply bypassing, and protection appropriate to the external connector.
Industrial Serial Console
MAX232DW can provide the physical-layer conversion for an industrial serial console that must remain compatible with RS-232 equipment. The two receivers accept inputs up to ±30 V, and the 1.3 V typical receiver threshold with 0.5 V typical hysteresis helps distinguish valid bipolar states. The device operates from a 4.5 V to 5.5 V supply and provides approximately ±9 V driver outputs. For production equipment, verify the device operating-temperature grade, enclosure grounding, cable routing, and connector-level surge or ESD protection before deployment.
Point-of-Sale and Peripheral Connectivity
The MAX232DW is appropriate for legacy point-of-sale peripherals that expose an RS-232 port but have no modern USB or Ethernet interface. Two driver and two receiver channels support bidirectional communication without requiring a separate level-shifter board. Its 8 mA typical supply current and single 5 V input simplify integration with embedded systems, while the 120 kbit/s maximum rate is suitable for many configuration and transaction protocols. Signal integrity depends on correct charge-pump capacitor placement and a properly implemented RS-232 connector, so those details should be checked before PCB release.
Data-Acquisition and Test Equipment
MAX232DW can bridge a test instrument or data-acquisition controller to an RS-232 service port while maintaining a conventional 5 V logic supply. The verified 120 kbit/s throughput is suitable for command traffic and moderate serial data transfers, and the dual-channel arrangement allows simultaneous transmit and receive paths. The approximately ±9 V outputs and ±30 V receiver input capability implement the voltage levels expected by legacy RS-232 equipment. In laboratory products, add suitable external line protection and verify that cable transients remain within the receiver and absolute-maximum limits documented by the manufacturer.
Legacy Service and Configuration Port
MAX232DW is useful when a modern controller must retain a service connector for programming, diagnostics, or configuration of legacy equipment. Its two-driver and two-receiver organization supports the normal transmit and receive paths without multiple level-conversion packages, while the 5 V supply operation fits many embedded platforms. The ±2 kV ESD protection stated for the MAX232 family adds an electrical safeguard, but it does not replace correctly selected external resistors, TVS devices, or protected connectors. Production validation should include noise immunity, ground-loop behavior, and system-level EMC testing.
Instrumentation and Control Panel
MAX232DW can serve as a compact RS-232 interface in instrumentation and control-panel products that use a 5 V controller and need to communicate with a host computer. The device handles the bipolar RS-232 voltage conversion while the host-side UART continues operating with TTL/CMOS logic. Its 120 kbit/s capability and two full-duplex channels are appropriate for status reporting and configuration commands. Because the MAX232 is an older RS-232 interface, engineers should assess whether RS-485, isolated UART, or another modern interface offers better noise immunity for long cables or electrically noisy industrial environments.
工程参考数据： MAX232DW ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | MAX232IDWR | MAX232EIDR | MAX232EIDWG4 | MAX232ECWE | MAX232AEUE+ |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SOIC-16 | SOIC-16 | SOIC-16 | SOIC-16 | SOIC-16 | SOIC-16 |
| Transceiver Configuration | 2 drivers and 2 receivers | Dual RS-232 driver/receiver | Dual RS-232 driver/receiver | Dual MAX232E-family driver/receiver | Dual MAX232-family driver/receiver | Dual RS-232 driver/receiver |
关键差异点
- Two complete RS-232 channels in one 16-pin package （对比 MAX232AEUE+)
- Documented 120 kbit/s operating rate （对比 MAX232EIDR)
- Wide receiver input capability （对比 MAX232ECWE)
- Single 5 V implementation （对比 MAX232EIDWG4)
设计说明
Do not substitute the MAX232E capacitor arrangement for the standard MAX232 without checking the manufacturer diagrams. The supplied MAX232EIDR description specifies 1.0 µF charge-pump capacitors, while the exact MAX232DW capacitor value is not present in the verified excerpts. Confirm the required capacitance, tolerance, voltage rating, and pins before ordering substitutes or changing an existing board.
Decouple the 5 V MAX232DW supply close to the device and preserve a low-impedance ground return between the transceiver and connector. The verified supply range is 4.5 V to 5.5 V, and typical supply current is 8 mA. Verify startup behavior, capacitor placement, and the charge-pump network using the manufacturer application guidance because the supplied excerpts do not include the recommended board-layout drawing.
Treat the external RS-232 connector as an electrically noisy boundary. Keep the MAX232DW interface path away from clocks, switching nodes, and sensitive analog inputs, and use a connector with a defined chassis-to-signal-ground strategy. The device's stated ±2 kV ESD rating does not eliminate the need for external protection when cables are long, exposed, or connected to poorly grounded equipment.
Place the charge-pump capacitors and supply-bypass components in accordance with the manufacturer datasheet, and keep the MAX232DW ground connection short. Do not infer the pinout from generic MAX232-family illustrations because suffix, package, and temperature variants can differ. Confirm the exact numbered pins for MAX232DW and verify that each UART TX and RX signal connects to the intended driver or receiver channel.
合规信息
The supplied search excerpts establish TIA/EIA-232-F and ITU Recommendation V.28 compatibility but do not provide RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. These fields remain unknown rather than being inferred.