ADM231LAN

Overview

The ADM231LAN is a dual transmitter and dual receiver RS-232 line transceiver from the ADM2xxL family, manufactured by Analog Devices Inc. It operates with a single 5 V supply (VCC) and requires an external positive supply voltage (V+) ranging from 7.5 V to 13.2 V. The device integrates an internal charge pump that generates a negative supply voltage (V-) for RS-232 signaling. It meets EIA-232-E and V.28 specifications with a data rate of up to 120 kbps and provides ±9 V output swing under typical conditions. The component utilizes Schmitt trigger inputs on receivers for noise immunity and features TTL/CMOS compatible logic levels.

Feature Summary

• Integrates internal charge pump circuitry to generate required negative supply voltage from a single positive input.
• Provides high noise immunity through Schmitt trigger inputs on all receiver channels.
• Includes internal pull-up resistors on transmitter inputs to prevent undefined states when unconnected.
• Features internal pull-down resistors on receiver inputs to ensure defined low logic levels.

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific ordering suffix 'LAN' against official manufacturer documentation to confirm package type and temperature range. Ensure the design accommodates the requirement for an external positive supply voltage between 7.5 V and 13.2 V, as this model differs from standard single-supply variants. Confirm compliance with relevant environmental regulations prior to integration.

Selection Notes

Select the ADM231LAN when a design requires two drivers and two receivers but lacks a dedicated +12 V rail, necessitating an external positive supply in addition to the 5 V logic supply. This part is suitable for applications where board space allows for external capacitors and a secondary voltage source. Compare against the ADM232L or ADM233L if only a single 5 V supply is available, as those models integrate full charge pumps internally.

Part Context

The ADM231LAN belongs to the ADM2xxL enhanced series, which improves upon the legacy AD2xx family with lower power consumption and faster slew rates. Unlike most members of the ADM2xxL family that operate solely on 5 V, the ADM231L and ADM239L are specifically designed to utilize an additional positive supply voltage. This configuration distinguishes it within the product line, targeting interfaces where mixed voltage availability exists.

Replacement Considerations

Public confirmed substitute part numbers: ADM231JN, ADM231AN, ADM231KN.