Analog Devices Inc./Maxim Integrated MAX213EEWI

Summary of the MAX213EEWI RS-232 Transceiver by Analog Devices/Maxim Integrated

The MAX213EEWI, designed and manufactured by Analog Devices/Maxim Integrated, is a high-performance RS-232 transceiver IC. Housed in a 28-pin SOIC package, this device delivers robust and reliable serial communication by supporting up to four transmitters and four receivers, compliant with EIA/TIA-232E and V.28 standards. Key attributes include integrated charge-pump circuitry for single-supply +5V operation and advanced electrostatic discharge (ESD) protection mechanisms that withstand events up to ±15kV, making the MAX213EEWI ideal for industrial and portable equipment faced with challenging electromagnetic environments.

Main Attributes and Functional Advantages of the MAX213EEWI

The MAX213EEWI transceiver integrates several features that simplify design and enhance longevity in demanding systems.

Advanced ±15kV ESD Human Body Model (HBM) protection at all transmitter and receiver interface pins protects sensitive equipment from everyday handling and repetitive cable insertions in field environments.

Integrated charge pump enables efficient dual ±10V internal voltage generation from a single +5V external supply, negating the need for external ±12V rails and thus reducing BOM costs and board complexity.

Low-power operation is ensured by a shutdown mode drawing as little as 15μA, supporting battery-powered and portable instrumentation.

CMOS/TTL compatible input thresholds allow seamless interfacing with modern logic families.

On-chip input pull-up resistors simplify unused transmitter handling, automatically biasing outputs for noise immunity.

Internal Design and Operational Overview of the MAX213EEWI

Internally, the MAX213EEWI comprises three principal functional blocks: charge pump voltage converters, RS-232 drivers, and CMOS/TTL logic receivers.

Charge pump voltage converters utilize external 0.1μF capacitors (C1–C4) to create stable ±10V rails from 5V supply, supporting RS-232 voltage requirements.

RS-232 driver outputs guarantee a swing of ±8V (typical) under normal loads, meeting strict EIA/TIA-232E specifications even under worst-case voltage and temperature conditions.

The receiver section converts incoming RS-232 levels into clean CMOS logic outputs, with input threshold levels (0.8V/2.4V) much tighter than RS-232 minimums for reliable noise rejection and compatibility.

Shutdown and enable controls empower engineers with flexible power management. In shutdown, most receivers enter high-impedance; notably, R4 and R5 remain active for external monitoring while consuming minimal power.

Electrical Specifications and Performance Data for the MAX213EEWI

The MAX213EEWI supports a wide supply voltage range (VCC: -0.3V to +6V absolute maximum) and maintains reliable operation between -40°C to +85°C ambient. The SOIC package supports up to 1W power dissipation with derated operation above +70°C.

Operational highlights include:

Driver output voltages: ±8V (typical), compliant with RS-232 minimums on 3kΩ loads

Data rates: guaranteed to 120kbps; optimal for standard serial communications in automation and data acquisition

Receiver propagation delay: typically 0.5μs normal, increasing to 4μs in shutdown for R4/R5

Input logic thresholds: CMOS/TTL compatible, ensuring interoperability with modern microcontrollers and FPGAs

These specifications enable reliable performance in electrically noisy environments and across wide application scenarios.

Packaging Format and Pinout Information for the MAX213EEWI

The MAX213EEWI is available in the 28-pin SOIC package, with dimensions conformant to JEDEC MS001 and MO-058AB standards. This package is preferred for its ease of handling and proven reliability in automated assembly lines.

Pin functions—transmit (T_IN/T_OUT) and receive (R_IN/R_OUT)—are logically arranged for board layout simplicity. The package accommodates necessary external capacitors used in charge-pump operation, with dedicated V+ and V- pins delivering the internally generated rails. Clear pin-out and top-view diagrams aid rapid integration into existing designs or new PCB layouts.

Use Cases and Design Recommendations for the MAX213EEWI

The MAX213EEWI excels in battery-powered, handheld, and portable diagnostic equipment demanding robust serial interfaces. Its 5V single-supply operation streamlines power architectures, while small-value (0.1μF) external capacitors save board area.

Designers should:

Select quality ceramic capacitors for C1–C4 to minimize ESR and voltage ripple, especially at low temperatures.

Increase charge-pump capacitor values (up to 10μF) if power is “borrowed” from V+ or Vrails.

Bypass VCC with at least 0.1μF to ground, or larger if supply noise is a concern.

Ensure each transmitter drives a single receiver; parallel transmitters for multi-receiver configurations.

Shutdown and enable logic allow integration of advanced power management—ideal for field instruments requiring remote wake or sleep as well as multi-port UARTs supporting wire-OR topologies.

Electrostatic Discharge Safeguards in the MAX213EEWI

The MAX213EEWI stands out for its robust ESD tolerance, vital for industrial settings where hot-plugging and operator contact can induce significant charge.

All transmitter and receiver pins withstand ±15kV ESD per Human Body Model.

The device is rated for ±8kV contact discharge and ±15kV air-gap discharge under IEC1000-4-2, facilitating equipment compliance with stringent standards without supplemental ESD components.

On-chip protection structures ensure stable, non-latching behavior after ESD events, maintaining system uptime and reliability in harsh and variable environments.

Comparable or Substitute Devices for the MAX213EEWI

For projects requiring alternative pin counts, or slightly different features, consider other members of the RS-232 transceiver family from Analog Devices/Maxim Integrated:

MAX202E, MAX206E, MAX208E, MAX211E (varied channel counts, package options)

MAX232E (16-pin, 1μF capacitors)

MAX241E (5 drivers/receivers, 28-pin, 1μF capacitors)

MAX203E, MAX205E (integrated charge-pump capacitors, reduced external component count)

All share the core features of ±15kV ESD protection and reliable 5V operation, and can be chosen based on specific channel requirements, board space, or integration levels.

Conclusion

: Evaluating the MAX213EEWI for Reliable RS-232 Communication

The MAX213EEWI provides engineers and procurement professionals with a robust, highly integrated solution for industrial RS-232 applications. Its superior ESD resilience, low power modes, and straightforward single-supply architecture directly address the challenges of modern device design and deployment—reducing system complexity, cost, and risk. For applications that demand reliable serial links in harsh electrical environments, the MAX213EEWI remains a compelling choice, further bolstered by a family of related transceivers for flexible design and long-term maintenance.