ADM238LAR

Overview

The ADM238LAR is a 5 V-powered CMOS RS-232 driver and receiver from Analog Devices Inc. It features four drivers and four receivers, operating from a single 5 V supply with internal charge pumps generating ±10 V levels. The device meets EIA-232-E specifications with a data rate of 120 kbps and ±9 V output swing. It requires four external 1 µF capacitors for operation. The component lacks low power shutdown or enable functions. It is available in 24-pin PDIP, CERDIP, and SOIC packages.

Feature Summary

• Integrates dual charge pump converters to generate required RS-232 voltage levels from a single 5 V digital supply
• Provides full EIA-232-E compliance with guaranteed output swings and input protection up to ±30 V
• Features Schmitt trigger inputs on receivers to ensure noise immunity and error-free reception

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific package variant (PDIP, CERDIP, or SOIC) corresponding to the 'AR' suffix against the manufacturer's ordering guide. Confirm temperature range requirements, as industrial versions may carry different suffixes. Ensure capacitor values match the datasheet recommendations for stable charge pump operation.

Selection Notes

Select this part when four independent transmit and receive channels are required without shutdown control. It is suitable for systems where a single 5 V supply is available but ±12 V rails are not. Compare against ADM237L if only drivers are needed, or ADM236L if low power shutdown functionality is required for battery applications.

Part Context

The ADM238L belongs to the ADM2xxL family of enhanced RS-232 transceivers. This family offers lower power consumption and faster slew rates compared to the legacy AD2xx series. It allows operation with smaller 1 µF capacitors, reducing board space requirements while maintaining robust communication interfaces for standard serial ports.

Replacement Considerations

ADM237L: Offers four drivers but zero receivers. ADM236L: Includes four drivers and three receivers plus shutdown/enable features. ADM232L: Provides two drivers and two receivers in a 16-pin package.