TRS3221EIDBR - 3-5.5V RS-232 Transceiver, ±15kV ESD | Texas Instruments
料号： TRS3221EIDBR ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.18 | $218.00 |
| 500 | $1.86 | $930.00 |
| 1,000 | $1.59 | $1,590.00 |
TRS3221EIDBR 概述
An RS-232 transceiver is a type of line driver/receiver IC that converts logic-level (typically 0/3.3 V or 0/5 V CMOS/CMOS) UART signals into the ±5 V to ±15 V voltage swings required by the TIA/EIA-232-F and ITU v.28 standards. It belongs to the broader interface-IC category, sitting between the UART block of a microcontroller/SoC and a DB-9 (or equivalent) connector on the serial port. Single-channel variants like the TRS3221E serve compact, point-to-point designs where two driver/receiver channels are not needed, helping shrink BOM cost and PCB area versus 2-channel parts.
Key features include 1 driver and 1 receiver per channel, a dedicated enable input for power management, an auto-powerdown mode that drops quiescent current to 1 µA typical when the cable is disconnected, and an always-active supplementary receiver that monitors the ring-indicator path even in shutdown. The device meets or exceeds the TIA/EIA-232-F and ITU v.28 electrical specifications, and is offered in industrial temperature grades of -40 °C to +85 °C. A high-speed pin-compatible upgrade, the TRSF3221E, is available where 1 Mbit/s operation is required.
The TRS3221E uses an on-chip switched-capacitor voltage converter with four external 0.1 µF charge-pump capacitors. The architecture tolerates supply rails as low as 3.0 V while still generating compliant ±5 V (minimum) RS-232 output swings, which is the headline advantage over legacy 5-V-only RS-232 transceivers. Drivers are slew-rate limited to keep EMI low, and the receivers include hysteresis to reject noise on long cables.
Typical applications include industrial single-port serial ports, point-of-sale terminals, handheld data collectors, factory automation equipment, medical instruments with DB-9 serial interfaces, and any embedded system that needs a robust RS-232 link from a 3.3 V or 5 V UART. Designers often pair this part with a TVS array for additional surge protection when the cable is exposed to outdoor or industrial transients.
When designing with the TRS3221EIDBR, place the four charge-pump capacitors (typically 0.1 µF X7R) as close as possible to the C0+, C0-, C1+, C1- pins to minimize supply ripple. Decouple VCC with a 0.1 µF + 1 µF combination near the pin, and respect the absolute-maximum ratings on the RS-232 outputs (typically ±13.2 V) by avoiding back-drive when the IC is unpowered.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替换替代料： TRS3221EIDBR ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
TRS3221ECDBR
✅ 直接替换📋 参考替代料（不在目录中）
TRS3221EIDBG4
✅ 直接替换📋 参考替代料（不在目录中）
MAX3221ECDBR
✅ 直接替换📋 参考替代料（不在目录中）
TRS3221EIDBR 规格参数
| 功能 | RS-232 Line Driver/Receiver (1 driver + 1 receiver) |
| Supply Voltage (VCC) | 3.0 V to 5.5 V |
| 数据速率 | 250 kbps |
| ESD Protection (HBM, RS-232 pins) | ±15 kV |
| ESD Protection (IEC 61000-4-2, contact) | ±8 kV |
| ESD Protection (IEC 61000-4-2, air-gap) | ±15 kV |
| Number of Drivers / Receivers | 1 / 1 |
| 工作温度范围 | -40 °C to +85 °C |
| 封装 | 16-SSOP (DB) |
| 安装类型 | Surface Mount |
| Charge Pump Capacitors Required | 4 x 0.1 µF external |
| Standards Compliance | TIA/EIA-232-F, ITU v.28 |
| Auto-Powerdown Quiescent Current | 1 µA typical |
| 使能引脚 | Yes (active-high, with complementary FORCEON/FORCEOFF logic) |
| RoHS 状态 | Compliant |
TRS3221EIDBR 引脚配置
| 引脚 1 | C1+ — Positive terminal of charge-pump flying capacitor 1 |
| 引脚 2 | V+ — Charge-pump generated +5.5 V supply for RS-232 drivers |
| 引脚 3 | C1- — Negative terminal of charge-pump flying capacitor 1 |
| 引脚 4 | C2+ — Positive terminal of charge-pump flying capacitor 2 |
| 引脚 5 | C2- — Negative terminal of charge-pump flying capacitor 2 |
| 引脚 6 | V- — Charge-pump generated -5.5 V supply for RS-232 drivers |
| 引脚 7 | DOUT2 — RS-232 driver output 2 (supplementary, always active) |
| 引脚 8 | RIN2 — RS-232 receiver input 2 (supplementary, always active) |
| 引脚 9 | ROUT2 — TTL/CMOS receiver output 2 (supplementary, always active) |
| 引脚 10 | DIN2 — TTL/CMOS driver input 2 (supplementary) |
| 引脚 11 | GND — Ground |
| 引脚 12 | VCC — 3.0 V to 5.5 V single supply input |
| 引脚 13 | DIN1 — TTL/CMOS driver input 1 (main) |
| 引脚 14 | ROUT1 — TTL/CMOS receiver output 1 (main) |
| 引脚 15 | RIN1 — RS-232 receiver input 1 (main) |
| 引脚 16 | FORCEOFF — Force-off input, active-low, drives drivers to high-Z |
典型应用
TRS3221EIDBR 适用于 6 应用s: Industrial Single-Port Serial Interface, Point-of-Sale Terminal, Handheld Data Collector / Barcode Scanner, Medical Instrument Serial Port, Factory Automation Controller / PLC, Embedded Debug / Programming Port.
Industrial Single-Port Serial Interface
The TRS3221EIDBR drives the RS-232 link between an industrial microcontroller's UART and a DB-9 connector on a PLC, sensor hub, or HMI panel. Its ±15-kV IEC 61000-4-2 ESD rating on the bus pins lets the design survive factory floor handling transients and most field surge events without an external TVS array. The 3.0-5.5 V supply range lets the same IC work whether the host SoC runs at 3.3 V or 5 V, and the 250 kbps data rate easily handles Modbus RTU, DF1, and most legacy SCADA protocols. Place the four 0.1 µF X7R charge-pump capacitors close to pins 1-6 to keep ripple under the TIA/EIA-232-F limit.
推荐
Point-of-Sale Terminal
POS terminals typically need one or two RS-232 ports to drive receipt printers, cash drawers, barcode scanners, or PIN pads. The TRS3221EIDBR's single-channel configuration fits compact terminals that only need a single port, while its 1 µA typical auto-powerdown current helps the terminal meet Energy Star idle-power targets when the cable is unplugged. The industrial -40 °C to +85 °C temperature grade covers kitchen and outdoor kiosk environments. Pair the IC with an external SMBJ-type TVS diode on each RS-232 pin for additional surge protection in cash-register environments subject to static discharge from customer interactions.
推荐
Handheld Data Collector / Barcode Scanner
Battery-powered handheld scanners and data collectors need a rugged RS-232 link to a charging/communications base. The TRS3221EIDBR operates from a single 3.0 V Li-ion rail without an external boost converter, simplifying the host board. Its 250 kbps data rate is more than adequate for barcode transmission and configuration command/response traffic. The always-active supplementary receiver (RIN2/ROUT2 in this part) lets the host SoC detect a plugged cable without waking the main UART, extending standby time. Industrial temperature rating ensures reliable operation in warehouses and outdoor logistics environments.
推荐
Medical Instrument Serial Port
Medical devices with RS-232 ports (patient monitors, infusion pumps, lab analyzers) benefit from the TRS3221EIDBR's integrated ±15-kV ESD protection that helps meet IEC 60601-1 ESD immunity requirements on the signal pins. The 16-SSOP package offers a small footprint that fits inside compact handhelds and ambulatory wearables. Designers should still add an external isolation barrier (digital isolator + isolated DC-DC) when the device must provide patient-applied-part isolation per IEC 60601-1, because the TRS3221EIDBR itself does not provide galvanic isolation. Use TVS diodes across the bus for additional surge protection on cables that may be plugged and unplugged many times per day.
推荐
Factory Automation Controller / PLC
Programmable Logic Controllers and small industrial PCs frequently expose a single RS-232 port for programming, debugging, or legacy equipment integration. The TRS3221EIDBR delivers a TIA/EIA-232-F compliant port from a 3.3 V or 5 V logic supply without requiring ±12 V rails, simplifying the PLC's internal power tree. The device's industrial -40 °C to +85 °C operating range and ±15-kV ESD rating let it survive the cabinet-installation and field-replacement handling common in factories. The on-chip charge pump and four small 0.1 µF capacitors fit easily on a PLC backplane where board space is constrained.
推荐
Embedded Debug / Programming Port
Many ARM Cortex-M and Microchip PIC32 development kits and reference boards expose an RS-232 debug port to a host PC. The TRS3221EIDBR is a common choice because it converts a 3.3 V MCU UART to RS-232 levels without external ±12 V supplies. The 16-SSOP footprint drops onto tiny evaluation boards, and the FORCEOFF/FORCEON logic lets the MCU put the port into shutdown when not in use, saving power in battery-powered debug tools. Pair with a UART-to-USB bridge IC for modern designs that no longer have a host-side DB-9, but keep the TRS3221EIDBR for legacy equipment that still uses real RS-232.
推荐
推荐产品汇总
工程参考数据： TRS3221EIDBR ——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 | TRS3221ECDBR | TRS3221EIDBG4 | TRS3221EIPWR | MAX3221ECDBR |
|---|---|---|---|---|---|
| Package | 16-SSOP (DB) | 16-SSOP (DB) - same | 16-SSOP (DB) - same | 16-TSSOP (PW) - different package | 16-SSOP (DB) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Maximum Data Rate | 250 kbps | 250 kbps | 250 kbps | 250 kbps | 250 kbps |
| Operating Temperature | -40 °C to +85 °C (industrial) | 0 °C to +70 °C (commercial) | -40 °C to +85 °C (industrial) | -40 °C to +85 °C (industrial) | 0 °C to +70 °C (commercial) |
| ESD Protection (IEC 61000-4-2, contact) | ±8 kV | ±8 kV | ±8 kV | ±8 kV | ±8 kV |
| ESD Protection (HBM) | ±15 kV | ±15 kV | ±15 kV | ±15 kV | ±15 kV |
| Auto-Powerdown Feature | Yes (1 µA typical) | Yes | Yes | Yes | Yes (with INVALID output) |
| Charge-Pump Capacitors Required | 4 x 0.1 µF | 4 x 0.1 µF | 4 x 0.1 µF | 4 x 0.1 µF | 4 x 0.1 µF |
关键差异点
- Industrial temperature range with ±15-kV IEC ESD （对比 TRS3221ECDBR)
- Always-active supplementary receiver for cable-presence detect （对比 MAX3221ECDBR)
- Single-rail supply eliminates ±12 V rails （对比 Legacy MAX232 (5 V only, no IEC ESD))
设计说明
The TRS3221EIDBR requires a clean 3.0-5.5 V supply decoupled with a 0.1 µF + 1 µF combination placed within 5 mm of the VCC pin (pin 12) and the GND pin (pin 11). The on-chip charge pump draws short current spikes at the charge-pump frequency; inadequate decoupling will show up as RS-232 output voltage droop and TIA/EIA-232-F compliance failures at heavy load. Use a low-ESR X7R ceramic for the 1 µF bulk capacitor to handle the transient current demands of the switched-capacitor converter.
Place the four charge-pump flying capacitors (C1, C2) as close as possible to pins 1-6 (C1+, V+, C1-, C2+, C2-, V-) using short, wide traces. The charge-pump switching nodes (C1+, C1-, C2+, C2-, V+, V-) carry fast edges; keep these traces short to minimize radiated EMI and to avoid injecting noise into nearby analog or RF circuitry. Star-ground the GND pin directly back to the host SoC's ground reference rather than chaining through a long ground path.
Do not back-drive the RS-232 outputs when VCC is removed: the absolute maximum ratings on the driver outputs are typically ±13.2 V, and a phantom-powered peripheral can drive voltages into unpowered drivers. Always include a power-on-reset strategy so the host SoC holds the FORCEOFF pin low (drivers high-Z) until VCC is stable. Also note that the 'E' suffix denotes the ±15-kV ESD variant - choosing the non-E TRS3221CDB drops the IEC ESD rating to ±2 kV, which is often insufficient for industrial environments.
合规信息
RoHS compliant per TI product page. Not AEC-Q100 qualified (this is an interface IC, not an automotive-grade part). IEC 61000-4-2 ESD rating ±8 kV contact / ±15 kV air-gap is integrated on the RS-232 bus pins per the manufacturer datasheet.
