ADM232LAR - 5V 2/2 RS-232 Transceiver, 120kB/s | Analog Devices
Артикул: ADM232LAR ✓ АктивенADM232LAR Обзор
An RS-232 transceiver is an interface IC that translates logic-level CMOS signals into the bipolar, +/- voltage signalling used by the RS-232 (EIA-232) standard. It sits between a UART or microcontroller and a physical cable. The wider ADM2xx family of line drivers and receivers was designed for EIA-232-E and V.28 communications interfaces, especially where +/-12 V supplies are not available, and the ADM232 in particular adds on-board DC-DC converters so no external charge-pump components or negative supply are needed.
Key features include a single 5 V power supply, on-board DC-DC converters with 9 V output swing capability, small 1 uF external capacitors, a low-power shutdown mode, 1 uA receiver operation while in shutdown, and receiver inputs tolerant to 30 V. The CMOS implementation keeps power consumption low compared with classic bipolar RS-232 transceivers.
Technically, the part uses an on-chip switched-capacitor DC-DC converter to generate the positive and negative rail voltages required for compliant RS-232 output levels, while the receiver stage is designed for high noise immunity and failsafe operation when the driver is disabled or the line is unconnected. The result is full RS-232 compliance from a single rail, which simplifies board layout and reduces the external component count to a small number of 1 uF capacitors.
Typical applications include industrial serial port adapters, instrumentation and test equipment, barcode and data-collection terminals, security and access-control panels, and general-purpose RS-232 links between a host UART and peripheral equipment where cable lengths and ground offsets require the +/- voltage swing of the RS-232 standard.
When designing around the ADM232LAR, place the 1 uF capacitors close to the charge-pump and driver pins, keep the RS-232 connector and cable routing separated from sensitive analog and clock traces to limit EMI, and account for the shutdown pin when the host needs to tri-state or power down the port. Because the receivers remain active in shutdown, the interface can still report line state while the driver current is minimized.
This page consolidates distributor listings, verified datasheet features, drop-in replacement options in the identical 16-SOIC footprint, and practical PCB and EMI design notes that are not assembled in one place in the original manufacturer documentation.
Аналоги без доработки для ADM232LAR — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
Варианты в этой серии
Модели той же серии, совместимые без доработки с ADM232LAR (тот же форм-фактор и посадочное место) — отличается по Package, Data Rate, Supply Voltage.
ADM232AARWZ
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
ADM202EARWZ
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
ADM232AARW
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
MAX232ECDWR
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
MAX232DR
✅ Прямая заменаУточнить цену
Открыть даташит →ADM232LAR Характеристики
| Напряжение питания | 5 V (single supply) |
| Transceiver Configuration | 2 drivers / 2 receivers (2/2) |
| Скорость передачи данных | 120 kB/s |
| Interface Standard Compliance | EIA-232-E and V.28 |
| Output Swing | 9 V with 5 V supply |
| On-Board DC-DC Converters | Yes |
| Required External Capacitors | 1 uF |
| Shutdown | Low power shutdown mode |
| Receiver Supply Current in Shutdown | 1 uA (receivers active in shutdown) |
| Receiver Input Voltage Tolerance | 30 V |
| Корпус | 16-lead SOIC (SOIC-16) |
| Количество выводов | 16 |
| Тип монтажа | Surface Mount |
| Technology | CMOS |
| Automotive Qualification (AEC-Q100) | not_applicable |
Руководство по цоколевке ADM232LAR в корпусе 16-lead soic (soic-16)
Цоколевка для ADM232LAR (корпус 16-lead soic (soic-16)). Нумерация выводов, функции и схемы подключения определены в техническом описании производителя. Обратитесь к нему для точного посадочного места и рекомендаций по пайке.
Нет подробных данных о распиновке для ADM232LAR.
Обратитесь к даташиту для полной конфигурации выводов.
Типичное применение
ADM232LAR подходит для 6 применениеs: Industrial Serial Port Expansion, Instrumentation and Test Equipment Control, Data Collection and Barcode Terminals, Security and Access Control Panels, Medical and Diagnostic Equipment Interfaces, Point-of-Sale and Retail Equipment.
Industrial Serial Port Expansion
The ADM232LAR adds a standards-compliant RS-232 port to a modern controller that only exposes a CMOS UART. Running from a single 5 V rail with on-board DC-DC converters removes the need for a negative supply rail, while the 120 kB/s rate comfortably covers legacy printer, console and programming port protocols. The 30 V receiver input tolerance protects the port when field cabling is connected to equipment running at the full +/-15 V RS-232 swing. With only 1 uF external capacitors, the charge-pump area stays small enough for compact control boards, and the low-power shutdown mode lets the port idle between transactions to reduce system current.
Рекомендуется
Instrumentation and Test Equipment Control
Laboratory instruments and automated test fixtures are frequently controlled from a host PC over RS-232, and the ADM232LAR is a straightforward way to bridge a 3.3 V or 5 V UART to that legacy bus. The 9 V output swing from a 5 V supply guarantees compliant levels even with several metres of cable and meaningful ground offsets, and the CMOS receiver front end rejects noise that would disturb a bare UART input. Because the receivers stay active during shutdown, a fixture controller can still poll line state for a connected-but-idle instrument. Two drivers and two receivers allow a single package to handle both a command channel and a status channel.
Рекомендуется
Data Collection and Barcode Terminals
Barcode scanners, badge readers and point-of-sale terminals often expose an RS-232 port as their legacy connectivity option. The ADM232LAR fits these designs because the whole interface runs from the same 5 V rail that powers the scanner electronics, with no external negative supply, and its 1 uF charge-pump capacitors are small enough for a handheld enclosure. The 120 kB/s rate is far above the throughput needed for scanned barcode payloads, so latency is dominated by the host protocol rather than the transceiver. The shutdown pin supports battery-powered terminals that must cut port current between scans.
Рекомендуется
Security and Access Control Panels
Access-control readers, door controllers and intercom stations commonly expose RS-232 to a head-end panel. The ADM232LAR is well suited to these panels because the receiver input can withstand 30 V, giving margin against mis-wired or externally powered RS-232 sources in the field, and the low-power shutdown mode lets idle card readers drop port current. Two drivers and two receivers in one 16-SOIC package let a single controller chip drive both a panel-side reader bus and an upstream supervisory link, reducing board area in tightly packaged door hardware.
Рекомендуется
Medical and Diagnostic Equipment Interfaces
Diagnostic and monitoring equipment often needs to interoperate with older RS-232 analysers and service tools. The ADM232LAR provides a compliant, low-noise RS-232 port from a single 5 V rail, with a CMOS receiver that is less susceptible to noise coupling from adjacent analog and motor circuitry than a bare UART input. The 30 V receiver tolerance provides a useful margin against transient coupling from hospital mains-fed equipment sharing the cable route, while the shutdown mode allows a portable analyser to conserve power between tests.
Рекомендуется
Point-of-Sale and Retail Equipment
Retail scales, customer displays and magnetic-stripe readers still rely on RS-232 in many installations. The ADM232LAR suits these designs because the single 5 V supply matches the logic rails typically found in point-of-sale hardware, and the 1 uF charge-pump capacitors avoid the bulk electrolytics that would otherwise dominate a small peripheral enclosure. The 120 kB/s rate covers scale weighing and transaction bursts with headroom, and the shutdown control allows peripherals to drop port current when idle at the counter.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для ADM232LAR — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар | ADM232AARWZ | ADM202EARWZ | ADM232AARW | MAX232ECDWR | MAX232DR |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Maxim Integrated | Maxim Integrated |
| Package | 16-lead SOIC (SOIC-16) | 16-lead SOIC - same | 16-lead SOIC - same | 16-lead SOIC - same | 16-lead SOIC - same | 16-lead SOIC - same |
| Transceiver Configuration | 2/2 (2 drivers, 2 receivers) | 2/2 full RS-232 | 2/2 full RS-232 | 2/2 full RS-232 | 2/2 full RS-232 | 2/2 full RS-232 |
Ключевые отличия
- Single 5 V rail with on-board DC-DC converters and 9 V output swing (против MAX232DR)
- Receivers stay active in low-power shutdown at 1 uA (против ADM202EARWZ)
- 30 V receiver input tolerance for field robustness (против MAX232ECDWR)
- 120 kB/s rate covers legacy serial protocols without adding a separate transceiver (против ADM232AARWZ)
Заметки по проектированию
Place the 1 uF charge-pump capacitors as close as possible to the corresponding IC pins, keeping traces short and symmetrical to minimise loop area on the switching node. The ADM232LAR generates its internal negative rail with an on-board DC-DC converter, so a long capacitor loop adds radiated EMI and can degrade output swing at the connector. Keep the RS-232 driver traces away from sensitive analog inputs and from crystal or clock routing to prevent coupled noise from appearing on the line.
RS-232 drivers deliberately swing about 9 V from a 5 V rail to meet EIA-232-E levels, so fast edge rates on TX lines create unavoidable EMI. Use a shielded connector shell tied to chassis ground where available, keep the cable run away from clocks and switching regulators, and avoid long unshielded PCB stubs of TX nets. The 120 kB/s data rate of the ADM232LAR is well within the range where these precautions are practical, so there is no need to trade signal integrity for throughput.
Because the ADM232LAR runs from a single 5 V rail and includes on-board DC-DC converters, the supply must be sized for the converter in addition to the logic load. Place a local 0.1 uF ceramic bypass capacitor at the supply pin in addition to the specified 1 uF charge-pump capacitors, and verify the 5 V rail tolerance at the IC, since the available headroom determines how close the drivers can reach the 9 V output swing. Enabling the shutdown pin during idle periods reduces port current while keeping the receivers active for line-state detection.
Do not treat the RS-232 receive pins as ordinary logic inputs: the ADM232LAR receivers are rated to 30 V, but the rest of the system is not. Also avoid confusing the ADM232 with the ADM202 when substituting, since the ADM202EARWZ shares the 16-SOIC footprint and the 2/2 configuration but has a different internal supply architecture. Finally, do not assume the MAX232-family replacements use the same 1 uF capacitor value; always re-read the charge-pump section of the replacement datasheet before releasing the PCB.
Информация о соответствии
The verified source data for ADM232LAR does not explicitly state RoHS, REACH, lead-free or halogen-free status; third-party comparison pages list RoHS/REACH fields for other ADM232 order codes but not for ADM232LAR itself, so all entries are left as unknown rather than assumed. The part is a commercial-grade RS-232 interface IC with no automotive qualification, so AEC-Q100 is not applicable.
