Texas Instruments MAX3232EIDR

Overview

MAX3232EIDR from Texas Instruments is a 3-V to 5.5-V dual RS-232 line driver and receiver IC with ±15-kV IEC 61000-4-2 ESD protection on RIN/DOUT pins, 250 kbit/s data rate capability, and integrated dual charge-pump circuit enabling single-supply operation. It provides bidirectional logic-to-RS232 level translation for UART interfaces in industrial and portable systems.

For engineers reviewing the MAX3232EIDR datasheet, MAX3232EIDR pinout, MAX3232EIDR application, or MAX3232EIDR equivalent, this page delivers verified technical context, exact package mapping (SOIC-16), confirmed pin functions, real-world timing and ESD performance, and two validated alternative parts for temperature-extended (-40°C to +85°C) RS-232 interface design.

Technical Context

The MAX3232EIDR implements a dual charge-pump architecture generating ±5.5 V rails from a single 3.3 V or 5 V supply, using four external 0.1 μF capacitors. Its drivers deliver ±5.4 V RS-232 output swing into 3-kΩ loads, while receivers accept ±25 V input ranges and provide TTL/CMOS-compatible outputs.

It operates across –40°C to +85°C, meets TIA/EIA-232-F and ITU V.28 standards, and features short-circuit protected outputs with 300 μA typical supply current. The device supports hot-swap safety: RIN/DOUT pins remain high-impedance and non-damaging when VCC = 0 V.

Key Specifications

Pinout & Package

MAX3232EIDR is housed in a 16-pin SOIC (D) package measuring 9.90 mm × 3.91 mm, RoHS-compliant, with NIPDAU lead finish and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RS-232 transceiver applications.

Compared with MAX3232EIDR, SN65C3232E offers higher speed headroom while retaining identical layout and BOM, whereas SP3232ECA-L provides automotive-grade validation at the cost of 67% higher quiescent current - both require no PCB revision but differ in thermal derating and long-term supply chain assurance.

Availability

MAX3232EIDR is available at Aetrix Electronics and suitable for industrial PLC communication, medical device serial interfaces, portable test equipment, and smart energy metering requiring stable component supply across extended temperature ranges.

Supply support for MAX3232EIDR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with over 90 years of innovation in precision analog design and industrial-grade reliability.

The MAX3232E series was designed specifically for robust, low-power RS-232 physical layer interfacing in industrial, medical, and portable electronics - emphasizing ESD resilience, single-supply operation, and extended temperature performance.

FAQ

What is the maximum data rate supported by the MAX3232EIDR?

The MAX3232EIDR supports a guaranteed maximum data rate of 250 kbit/s under recommended operating conditions (VCC = 3.3 V or 5 V, CL = 1000 pF, RL = 3 kΩ). This is sufficient for standard UART baud rates up to 230.4 kbit/s. While some units may operate beyond this, TI specifies 250 kbit/s as the production-tested limit with full timing margin and EMI compliance.

Does the MAX3232EIDR require external capacitors, and what values are needed?

Yes, the MAX3232EIDR requires four external 0.1 μF ceramic capacitors (C1+, C1−, C2+, C2−) for charge-pump operation. For VCC = 3.3 V ± 0.3 V, all four capacitors are 0.1 μF. For VCC = 5 V ± 0.5 V, C1 should be 0.047 μF and C2–C4 0.33 μF. A 0.1 μF bypass capacitor between VCC and GND is also mandatory for stability.

Is the MAX3232EIDR pin-compatible with older MAX3232 variants?

Yes, the MAX3232EIDR is pin-compatible with legacy MAX3232C/D variants in the same SOIC-16 (D) package. However, it adds enhanced ±15 kV IEC 61000-4-2 ESD protection and tighter electrical specifications - no PCB changes are needed when upgrading from MAX3232CDR or MAX3232CDBR, provided the operating temperature range (–40°C to +85°C) is acceptable.

What is the purpose of the V+ and V− pins on the MAX3232EIDR?

V+ and V− are internal charge-pump output nodes - they are not user-supplied rails. These pins connect exclusively to the external 0.1 μF capacitors (C1 and C2) and must never be loaded or tied to external supplies. Their function is to generate the ±5.5 V voltages required to drive RS-232 compliant outputs from a single 3.3 V or 5 V input.

Can the MAX3232EIDR operate with a 3.3 V supply while interfacing with 5 V logic systems?

Yes, the MAX3232EIDR accepts 5 V logic-level inputs on DIN1 and DIN2 even when powered from a 3.3 V supply - a key feature enabling mixed-voltage system integration without external level shifters. Its ROUT outputs swing rail-to-rail (0.4 V low, VCC − 0.6 V high), so at 3.3 V VCC, outputs are compatible with 3.3 V logic families.