ADM232LAR

Overview

The ADM232LAR is a CMOS RS-232 line driver and receiver manufactured by Analog Devices Inc. It operates from a single 5 V power supply and supports data rates up to 120 kbps. The device integrates on-board DC-to-DC converters that generate ±9 V output swings using small 1 µF external capacitors. It features two drivers and two receivers, meeting all EIA-232-E and V.28 specifications. The component includes ±30 V receiver input protection and latch-up free design characteristics.

Feature Summary

• Single 5 V power supply operation with integrated charge pump voltage conversion
• Low power shutdown mode reducing current consumption to less than 1 µA
• Schmitt trigger inputs providing noise immunity for reliable signal reception
• Internal pull-up and pull-down resistors on transmitter and receiver inputs

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific suffix 'L' indicates the low-power variant requiring 1 µF capacitors rather than the standard ADM232A which uses 0.1 µF capacitors. Confirm the package type matches the required PCB layout, as the L-series is available in multiple pin configurations including SOIC and PDIP. Ensure the industrial temperature range rating aligns with the environmental conditions of the target application.

Selection Notes

Select the ADM232LAR when a single 5 V supply is available but bipolar RS-232 voltages are required without external high-voltage sources. This part is suitable for applications prioritizing lower power consumption compared to non-L variants. Verify if the 120 kbps speed meets system requirements, as higher-speed alternatives like the ADM232A exist. Consider the shutdown feature if battery life is a critical constraint in the design.

Part Context

The ADM232LAR belongs to the ADM2xxL family of enhanced CMOS RS-232 transceivers. This family serves as an upgrade to the older AD2xx series, offering improved power efficiency and faster slew rates. The L designation specifically denotes components optimized for low-power operation and compatibility with smaller external capacitors, distinguishing them from the standard ADM232A series.

Replacement Considerations

ADM232AARNZ

FAQ

What is the maximum data rate supported by the ADM232LAR?

The ADM232LAR supports transmission rates up to 120 kbps.

Does the ADM232LAR include a shutdown mode?

Yes, the ADM232L family includes a low power shutdown mode that reduces power dissipation significantly.

What external capacitor values are required for the charge pump?

The ADM232LAR requires four 1 µF external capacitors for its internal DC-to-DC converters.