ADM239LAR

Overview

The ADM239LAR is a CMOS RS-232 driver and receiver manufactured by Analog Devices Inc. It operates from dual supplies: VCC at 5 V ± 10% and V+ ranging from 7.5 V to 13.2 V. The device integrates three transmitters and five receivers, requiring only two external capacitors for its internal charge pump voltage converter. It supports data rates up to 120 kbps and features an active-low enable input for controlling receiver outputs. The component meets EIA-232-E and V.28 specifications with ±9 V output swings and ±30 V receiver input protection.

Feature Summary

• Integrates three drivers and five receivers for comprehensive serial communication interfaces
• Includes internal charge pump circuitry generating negative supply from positive input
• Features active-low enable control for managing receiver high-impedance states
• Provides Schmitt trigger inputs on receivers to ensure noise immunity

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific package variant corresponding to the 'LAR' suffix against the manufacturer's ordering guide. Confirm that the design accommodates the required external 7.5 V to 13.2 V supply rail for the V+ pin, as this model differs from single-supply variants in the family.

Selection Notes

Select this part when a system requires multiple receiver channels alongside standard transmission capabilities. Ensure the power architecture can support the separate V+ supply range of 7.5 V to 13.2 V. This component is suitable for applications needing receiver bus sharing via the enable pin.

Part Context

The ADM239L belongs to the ADM2xxL family of enhanced RS-232 transceivers designed for 5 V digital systems. Unlike single-supply members, this variant utilizes an external positive voltage source combined with an internal inverter to generate the necessary bipolar rails for RS-232 signaling standards.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.