ADM202EAN

Overview

The ADM202EAN is a dual-channel RS-232 line driver and receiver manufactured by Analog Devices Inc. It operates from a single 5 V power supply (4.5 V to 5.5 V) with a typical quiescent current of 6 mA under no-load conditions. The device supports data rates up to 230 kbps and features internal charge-pump circuitry requiring four external 0.1 µF capacitors. It provides ±9 V output voltage swings and includes robust ESD protection rated at ±15 kV for air discharge and ±8 kV for contact discharge, alongside EFT immunity of ±2 kV.

Feature Summary

• Compliant with the EU EMC directive (89/336/EEC) regarding electromagnetic emissions and immunity.
• Integrated electrostatic discharge protection on all I/O lines exceeding ±15 kV air-gap discharge standards.
• High-speed transmission capability supporting data rates up to 230 kbps with controlled slew rates.
• Internal Schmitt-trigger receivers with hysteresis to ensure error-free reception of noisy signals.

Applications

• General-purpose RS-232 data links
• Portable instruments
• Personal Digital Assistants (PDAs)

Procurement Notes

Verify the specific package type required, as the datasheet lists multiple options including wide SOIC, narrow SOIC, TSSOP, and PDIP. Confirm that the ordering suffix corresponds to the desired physical footprint and lead form. Ensure compatibility with existing PCB layouts if replacing older generation transceivers like the MAX202E or ADM232L.

Selection Notes

Select this component when harsh electrical environments require high immunity to ESD and fast transients without external shielding. It serves as a direct pin-compatible upgrade for legacy RS-232 interfaces. Consider the TSSOP option for space-constrained designs, noting it is 44% smaller than the standard SOIC package while maintaining identical functionality.

Part Context

The ADM202E is part of the ADM202E/ADM1181A family, designed as a robust enhancement to the ADM230–ADM241 series. It offers improved electromagnetic compatibility compared to earlier generations. The device is functionally similar to the ADM1181A but differs in internal capacitor connection configurations for the charge pump.

Replacement Considerations

Publicly confirmed pin-compatible replacements include the ADM202, ADM232L, MAX202E, MAX232E, LTC1181A, and LT1181A. Verify that the substitute device meets the same ±15 kV ESD protection requirements and 230 kbps data rate specifications.

FAQ

How does the ADM202EAN handle unconnected receiver inputs?

Each RS-232 receiver input contains an internal 5 kΩ pull-down resistor to ground. This ensures that unconnected inputs are pulled to a Logic 1 output level, preventing floating states.

What is the maximum data rate supported by this device?

The device guarantees a maximum data rate of 230 kbps under worst-case loading conditions, making it suitable for high-speed ISDN modem standards.

Does the device require additional filtering for conducted emissions?

No additional filtering or decoupling is required beyond the recommended four 0.1 µF charge-pump capacitors. The design minimizes switching glitches to stay within EN55022 limits.