ADM236LJR - 5V 120kbps RS-232 Transceiver | Analog Devices
料号： ADM236LJR ✓ 量产中ADM236LJR 概述
An RS-232 transceiver is an interface IC that combines line drivers, line receivers, and voltage-level translation for serial communications. In the product hierarchy, it belongs to interface ICs, data converters and interface devices, and semiconductor components. The ADM2xx family is intended for systems where conventional negative supply voltages are unavailable. The integrated converter approach reduces board complexity by producing bipolar RS-232 levels internally while the external system operates from 5 V.
Key features include a maximum stated data rate of 120 kB/s, on-board DC-DC conversion, approximately 9 V output swing from a 5 V supply, and 1 µF external charge-pump capacitors. The low-power shutdown function reduces power dissipation to less than 5 µW, making the interface suitable for portable and power-conscious equipment. Two receivers remain active during shutdown, allowing selected incoming signals to be monitored while most of the transceiver is inactive.
The receiver input withstands voltages up to 30 V, providing protection in industrial environments where connected equipment can present larger voltage excursions. The manufacturer datasheet also states that the drivers maintain approximately ±5 V signal levels at data rates up to 100 kbps under worst-case loading. These characteristics make the ADM236LJR useful where a compact, single-supply RS-232 connection is required without relying on an external bipolar power supply.
Typical applications include industrial serial-port equipment, point-of-sale terminals, data acquisition systems, test and measurement instruments, security-system controllers, and battery-powered communication equipment. Designers should verify line capacitance, cable length, driver loading, and receiver input levels against the application’s EIA-232-E requirements. The shutdown-control logic and the behavior of the two always-active receivers should also be checked to ensure they meet the system power-management sequence.
For a robust layout, place the 1 µF charge-pump capacitors close to their associated IC pins and keep the high-voltage driver outputs away from sensitive input traces. Confirm that the external supply remains stable during data transmission, and account for the positive temperature coefficient of RS-232 thresholds when designing across the full operating environment. The exact pin names, package dimensions, and full electrical limits should be confirmed against the official Analog Devices datasheet before layout release.
This page combines the verified Analog Devices datasheet information, current distributor availability, same-package alternatives, and practical design guidance. It highlights the ADM236LJR’s single-supply operation, integrated DC-DC conversion, shutdown behavior, and interface trade-offs in a format intended for component selection and PCB design decisions.
直接替换替代料： ADM236LJR ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： ADM236LJR （相同外形与封装尺寸） ——差异在于 Package, Product Type.
ADM235LJR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
ADM237LJR
✅ 直接替换 ⚠️ 规格未核验联系询价
查看数据手册 →ADM238LJR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
ADM241LJR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MAX236EWG+
✅ 直接替换📋 参考替代料（不在目录中）
ADM236LJR 规格参数
| Product Type | +5 V powered CMOS RS-232 drivers/receivers |
| 电源电压 | 5 V |
| Maximum Data Rate | 120 kB/s |
| Driver Count | 3 |
| Receiver Count | 3 |
| Supported Standards | EIA-232-E and V.28 |
| DC-DC Converter | On-board |
| RS-232 Output Swing | 9 V |
| Driver Signal Level | Approximately ±5 V at data rates up to 100 kbps under worst-case loading |
| Charge-Pump Capacitor | 1 µF |
| Shutdown Power Dissipation | Less than 5 µW |
| Receivers Active During Shutdown | 2 |
| Maximum Receiver Input Voltage | 30 V |
| 封装 | 20-pin SOIC |
| 安装类型 | Surface mount |
| Transceiver Functions | 3 drivers and 3 receivers |
| Supplier | Rochester Electronics, LLC |
ADM236LJR 20-pin soic 引脚配置指南
ADM236LJR（20-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： ADM236LJR.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ADM236LJR 适用于 6 应用s: Industrial RS-232 Equipment, Data Acquisition and Test Systems, Battery-Powered Portable Devices, Point-of-Sale Terminals, Security and Surveillance Systems, Network and Communication Equipment.
Industrial RS-232 Equipment
The ADM236LJR fits industrial serial-port equipment because a single 5 V rail produces the bipolar RS-232 signal levels through an on-board DC-DC converter. Its three drivers and three receivers support several command and status channels in a compact 20-pin SOIC footprint, while the receiver input tolerance of up to 30 V improves robustness against larger excursions on industrial connections. The 120 kB/s maximum data rate is appropriate for configuration links, service ports, and supervisory communication. Designers should preserve the specified 1 µF charge-pump capacitor layout and verify that cable loading and grounding comply with EIA-232-E expectations.
Data Acquisition and Test Systems
The ADM236LJR is suitable for data-acquisition and test systems that expose legacy RS-232 ports while the instrument itself uses modern 5 V logic. Three transmit and three receive channels can connect equipment commands, acknowledgments, measurement data, and status signals without requiring multiple single-channel transceivers. The 120 kB/s rate supports instrument-control traffic, and the approximately 9 V output swing helps retain usable signal margins over a cable. The internal converter removes external +12 V and -12 V rails, but the design must still account for connector ground, cable length, and transient protection at the exposed interface.
Battery-Powered Portable Devices
The ADM236LJR supports battery-powered portable equipment through its low-power shutdown mode, which reduces power dissipation to less than 5 µW according to the Analog Devices datasheet. Two receivers remain active during shutdown, potentially supporting monitoring or wake-up logic without keeping every driver and receiver operational. The single 5 V architecture is convenient for portable products that cannot generate external negative voltage rails. Actual battery-life calculations should include leakage and the current drawn by the two active receivers because the less-than-5-µW figure describes the quoted low-power shutdown dissipation rather than every operating condition.
Point-of-Sale Terminals
Point-of-sale terminals often need several RS-232 links to a printer, scanner, display, or service connector, and the ADM236LJR provides three drivers and three receivers in one 20-pin SOIC package. Its on-board DC-DC conversion allows the terminal to operate from 5 V while producing approximately 9 V RS-232 output swing. The 120 kB/s maximum rate is more than adequate for typical peripheral command and status traffic. Layout should keep charge-pump components close to the IC and maintain a low-impedance connection between the transceiver ground and the connector reference ground.
Security and Surveillance Systems
The ADM236LJR can support legacy control and status links in security and surveillance systems that need multiple RS-232 channels. The device's receiver input tolerance of up to 30 V adds margin when cable-connected equipment presents larger transients, while the integrated DC-DC converter simplifies the internal 5 V power architecture. A 120 kB/s interface rate is suitable for configuration and monitoring traffic rather than high-bandwidth video transport. Engineers should add suitable external surge and ESD protection according to the installation environment and keep those protective components near the external connector.
Network and Communication Equipment
The ADM236LJR is applicable to communication equipment and network-support hardware that retains an RS-232 management or service interface. Three channels allow concurrent command, diagnostic, and status signals while the integrated converter eliminates a separate bipolar supply. The approximately ±5 V driver levels cited up to 100 kbps under worst-case loading provide useful margin for management links operating below that rate. The 120 kB/s ceiling must be treated as a maximum specification, and the external shield, ground, and connector arrangement should be designed for the cable environment rather than assuming logic-level signals.
工程参考数据： ADM236LJR ——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 | ADM235LJR | ADM237LJR | ADM238LJR | ADM241LJR | MAX236EWG+ |
|---|---|---|---|---|---|---|
| Package | SOIC-20 | SOIC-20 | SOIC-20 | SOIC-20 | SOIC-20 | SOIC-20 listed for compatibility review; supplied comparison snippet describes a 24-pin WSOIC package |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Maxim Integrated |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V | 5 V | 5 V |
| Standards Compliance | EIA-232-E and V.28 | EIA-232-E and V.28 | EIA-232-E and V.28 | EIA-232-E and V.28 | EIA-232-E and V.28 | EIA/TIA-232-E and V.28/V.24 |
关键差异点
- Integrated single-supply DC-DC conversion （对比 MAX236EWG+)
- Defined low-power shutdown behavior （对比 ADM238LJR)
- Specified 120 kB/s operation （对比 ADM237LJR)
- Higher receiver input tolerance （对比 ADM241LJR)
设计说明
Place the specified 1 µF charge-pump capacitors close to the ADM236LJR pins identified by the official datasheet. Keep the associated switched-capacitor traces short, preserve the recommended ground return, and avoid routing them beneath the RS-232 driver outputs. Because the on-board DC-DC converter generates the bipolar signal voltage, poor capacitor placement can increase converter noise and reduce available output margin.
Do not assume that the less-than-5-µW shutdown figure represents total device consumption in every operating mode. Two receivers remain active during shutdown, and their current must be included in battery-life calculations. Also distinguish the 120 kB/s maximum data rate from the manufacturer statement that ±5 V signal levels are maintained up to 100 kbps under worst-case loading; these are separate conditions.
Verify the exact receiver thresholds, output levels, enable polarity, and pin mapping against the official datasheet before assigning any substitute part. The ADM235LJR, ADM237LJR, ADM238LJR, ADM241LJR, and MAX236EWG+ entries are alternatives for engineering review, not a guarantee that channel signals, shutdown behavior, and footprint are interchangeable without a complete schematic comparison.
Connect the transceiver ground to the RS-232 connector reference ground through a short, low-impedance path. Keep high-voltage driver outputs away from receiver and logic traces, and use the connector shield or chassis connection according to the installation's EMC strategy. External surge or ESD protection may be required for industrial cables; its voltage rating and capacitance should be selected so it does not prevent the interface from meeting its required data rate.
合规信息
The supplied verified results do not state product-specific RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. These fields remain unknown rather than being inferred from general manufacturer practices.
