MAX3221IDB - 250kbps Single RS-232 Transceiver | TI
料号： MAX3221IDB ✓ 量产中MAX3221IDB 概述
An RS-232 transceiver is an interface integrated circuit that converts logic-level UART signals into RS-232 voltage levels and converts returning RS-232 signals back into logic-compatible levels. The MAX3221IDB sits between an asynchronous communication controller and a serial connector, combining a line driver, line receiver, and dual charge-pump circuit in one compact package.
Its headline operating specifications are a 3 V to 5.5 V supply range, 250 kbps maximum signaling rate, and ±15 kV pin-to-pin ESD protection. The integrated dual charge-pump circuit generates the positive and negative voltage levels required for RS-232 transmission without requiring an external supply. A dedicated receiver-enable pin supports controlled reception when the host does not need the incoming signal continuously.
The device meets the electrical requirements stated for TIA/EIA-232-F and is intended for asynchronous serial communication. Because the MAX3221IDB combines only one transmit channel and one receive channel, it is most appropriate where the system needs a compact point-to-point RS-232 interface rather than multiple channels. Its 16-pin SSOP format also supports conventional surface-mount PCB assembly.
Typical uses include industrial serial controllers, point-to-point data links, configuration-port interfaces, test equipment, and embedded systems that communicate with RS-232 equipment. The 250 kbps capability is suitable for common serial-port baud rates while the internal charge pumps simplify implementation compared with a discrete level-shifting circuit.
When laying out the circuit, place the charge-pump capacitors and interface protection components close to their associated pins, and route the driver and receiver traces away from sensitive analog circuitry. Confirm connector-level signal integrity with the intended cable, baud rate, grounding arrangement, and ESD environment before production release.
This page combines the manufacturer specifications, drop-in replacement information, application guidance, and design considerations needed to evaluate the MAX3221IDB for a single-channel RS-232 interface. Use the Request a Quote form on this page for current commercial availability and lead-time information.
直接替换替代料： MAX3221IDB ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
MAX3221CAE+T
✅ 直接替换📋 参考替代料（不在目录中）
MAX3221CDBR
✅ 直接替换📋 参考替代料（不在目录中）
ICL3221EIAZ-T
✅ 直接替换📋 参考替代料（不在目录中）
MAX3221IDB 规格参数
| Product Type | Single-channel RS-232 line driver/receiver |
| Supply Voltage Range | 3 V to 5.5 V |
| Maximum Data Rate | 250 kbps |
| ESD Protection | ±15 kV pin to pin |
| Driver Count | 1 driver |
| Receiver Count | 1 receiver |
| Receiver Enable | Dedicated enable pin |
| Charge-Pump Architecture | Dual charge-pump circuit |
| Interface Standard | TIA/EIA-232-F |
| 封装 | 16-pin SSOP |
| 安装类型 | Surface mount |
| Channel Count | 1 channel |
| RoHS Compliance | unknown |
| REACH Compliance | unknown |
MAX3221IDB 16-pin ssop 引脚配置指南
MAX3221IDB（16-pin ssop 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： MAX3221IDB.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MAX3221IDB 适用于 6 应用s: Industrial Point-to-Point Serial Links, Embedded Configuration Ports, Test and Measurement Equipment, Data Acquisition Modules, Security and Access-Control Terminals, Portable Instrumentation.
Industrial Point-to-Point Serial Links
The MAX3221IDB fits a point-to-point industrial serial link that requires one transmit channel and one receive channel at up to 250 kbps. Its 3 V to 5.5 V supply range supports both 3.3 V and 5 V controller environments, while the dual charge-pump circuit supplies the bipolar voltage levels required by RS-232. The dedicated receiver-enable function helps a controller suppress or enable incoming data when needed. The ±15 kV pin-to-pin ESD protection adds useful protection on connector-facing nets, although board-level grounding, cable selection, and surge requirements still need separate evaluation.
推荐
Embedded Configuration Ports
The MAX3221IDB is appropriate for an embedded controller that exposes a configuration or maintenance port through an RS-232 connector. A single driver and receiver are sufficient for a two-wire serial service interface, and the 250 kbps rate provides ample margin for firmware-loader traffic and command exchanges. Running the transceiver from 3 V to 5.5 V allows it to sit beside either 3.3 V or 5 V digital logic. The integrated charge pumps reduce the number of external bias networks, but the board must still follow the manufacturer capacitor and layout guidance to achieve reliable operation and expected ESD resilience.
推荐
Test and Measurement Equipment
The MAX3221IDB can provide the RS-232 connection between test equipment and a PC or controller when a single serial channel is required. Its 250 kbps maximum data rate is well matched to command and measurement-data transfers that do not require continuous multi-channel throughput. The 3 V to 5.5 V operating range simplifies integration with mixed-voltage test hardware, and the dedicated receiver enable offers control over input handling. For laboratory and production equipment, preserve the RS-232 common-ground arrangement, validate cable behavior, and keep the transceiver away from high-energy switching nodes to minimize noise and ground-current problems.
推荐
Data Acquisition Modules
The MAX3221IDB is suitable for a compact data-acquisition module that sends commands or status to a host over RS-232. One receive path handles host requests, while one driver path returns readings or diagnostics at up to 250 kbps. The single-channel structure avoids unnecessary board area compared with a multi-channel transceiver, and the 3 V to 5.5 V supply range accommodates several embedded controller platforms. The ±15 kV ESD rating is especially relevant when the serial connector is externally accessible. Engineers should still evaluate enclosure grounding, cable transients, isolation, and the need for surge protection according to the installation environment.
推荐
Security and Access-Control Terminals
The MAX3221IDB can connect a door controller, access-control terminal, or alarm interface to an RS-232 supervisory system. The 250 kbps rate supports event reporting and command traffic, while the dedicated receiver enable lets the terminal control reception during selected operating states. The ±15 kV ESD protection is useful at an exposed connector-facing port, and the compact 16-pin SSOP preserves board area in space-constrained terminals. The finished product still needs an enclosure, defined protective-earth strategy, cable-length validation, and environmental surge testing; connector protection alone does not replace those system-level safeguards.
推荐
Portable Instrumentation
The MAX3221IDB fits portable instruments that communicate with a host computer over a single RS-232 port. Its 3 V minimum supply supports lower-voltage embedded systems, while the 5.5 V maximum provides flexibility across 3.3 V and 5 V rails. At 250 kbps, the device handles typical instrument command and sample-status traffic without multiplexing several RS-232 channels. Its integrated dual charge pumps simplify the power section, although a portable product may require careful grounding between a host and a separately powered instrument. Use twisted-pair cabling, validate common-mode behavior, and test with the intended host driver because software flow control cannot compensate for every physical-layer fault.
推荐
推荐产品汇总
工程参考数据： MAX3221IDB ——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 | MAX3221CAE+T | MAX3221CDBR | ICL3221EIAZ-T |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated |
| Package | 16-SSOP | 16-SSOP | 16-SSOP | 16-SSOP |
| Product Type | Single-channel RS-232 transceiver | Single-channel RS-232 transceiver | Single-channel RS-232 transceiver | Single-channel RS-232 transceiver |
| Maximum Data Rate | 250 kbps | 250 kbps class | 250 kbps class | 250 kbps class |
| Driver and Receiver Count | 1 driver and 1 receiver | 1 driver and 1 receiver | 1 driver and 1 receiver | 1 driver and 1 receiver |
关键差异点
- Documented 250 kbps single-channel performance （对比 ICL3221EIAZ-T)
- Wide 3 V to 5.5 V supply operation （对比 MAX3221CAE+T)
- Pin-to-pin ESD protection on serial-port connections （对比 MAX3221CDBR)
设计说明
Place the charge-pump capacitors and supply-decoupling capacitors close to their designated IC pins, using the shortest practical ground-return paths. Follow the Texas Instruments MAX3221 application circuit for capacitor values and pin assignments. Keep the connector-side driver and receiver traces away from clocks, ADC inputs, precision references, and switching-regator power nodes to reduce ground bounce and charge-pump coupling into sensitive circuits.
Route the RS-232 connector nets as a matched, twisted pair where possible, and terminate the ground reference according to the cable and enclosure strategy. Avoid long unprotected stubs between the transceiver and connector. Because the MAX3221IDB uses positive and negative RS-232 voltage levels, do not treat the driver output as a direct logic-level UART signal; maintain separation between logic-side and connector-side nets during layout.
Do not assume that a matching SSOP outline guarantees a functional substitute. Verify enable polarity, charge-pump capacitor values, supply limits, receiver thresholds, maximum data rate, operating-temperature range, and ESD rating for each alternative. The MAX3221CAE+T and ICL3221EIAZ-T are identified as drop-in candidates, but production approval should still include signal-integrity and cable testing at the intended baud rate.
Provide a low-impedance ground reference between the transceiver ground and the connector shield according to the system grounding policy; simply bonding shield and signal ground can create unwanted current paths in some installations. Validate conducted emissions and susceptibility with the production cable and enclosure. If either device is separately powered, use an isolated interface or protection strategy rather than allowing an unpredictable ground potential to damage the transceiver.
合规信息
The manufacturer description confirms TIA/EIA-232-F compliance, but no explicit RoHS, REACH, halogen-free, lead-free, conflict-minerals, or automotive-qualification statement is confirmed. AEC-Q100 is not applicable to this general-purpose RS-232 interface unless a separate automotive-qualified ordering variant is specified.
