ADM239LJRZ-REEL

Overview

The ADM239LJRZ-REEL is a CMOS RS-232 transceiver from Analog Devices, designed for EIA-232-E and V.28 communication interfaces. It features three drivers and five receivers in a 24-pin SOIC package. The device operates with a 5 V supply (VCC) and requires an external positive supply between 7.5 V and 13.2 V (V+) to generate the internal negative charge pump voltage. It supports data rates up to 120 kbps and includes an active-low enable input for receiver control. The part meets all EIA-232-E specifications with ±9 V output swings and ±30 V receiver input protection.

Feature Summary

• Integrated negative charge pump converter generates required negative supply voltage from external positive input
• Active-low enable input allows receiver outputs to be placed in high impedance state for bus sharing
• Schmitt trigger inputs on receivers provide noise immunity and hysteresis for slow transition signals
• Internal pull-up resistors on transmitter inputs ensure defined states when unconnected

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific ordering suffix matches the reel packaging configuration required for your assembly line. Confirm that the component version corresponds to the industrial temperature range if operating outside commercial limits. Ensure the datasheet revision aligns with the manufacturing date code to validate electrical parameters.

Selection Notes

Select this component when a single 5 V digital supply is available but a separate positive rail between 7.5 V and 13.2 V exists for the charge pump. It is suitable for designs requiring multiple receiver channels with bus-sharing capabilities via the enable pin. Verify that the external capacitor requirements for the charge pump fit within the board space constraints.

Part Context

This component belongs to the ADM2xxL family of low-power RS-232 transceivers. It serves as an enhanced upgrade to the older AD2xx series, offering lower power consumption and faster slew rates. Unlike other members of the L-family that use only a 5 V supply, the ADM239L specifically utilizes an external positive supply to drive its internal charge pump circuitry.

Replacement Considerations

ADM239LJRZ