ADM236LJR

Overview

The ADM236LJR is a CMOS RS-232 driver and receiver manufactured by Analog Devices Inc. It operates from a single 5 V power supply, utilizing internal charge pumps to generate the required ±10 V levels for EIA-232-E compliance. The device integrates four drivers and three receivers, supporting data rates up to 120 kbps. Key electrical parameters include a typical output voltage swing of ±9 V, a maximum shutdown supply current of 10 µA, and an input logic threshold high of 2.0 V. It features Schmitt trigger inputs with 0.65 V hysteresis and supports low power shutdown mode.

Feature Summary

• Integrates on-board DC-to-DC converters to enable operation from a single 5 V supply without external high-voltage rails.
• Features a low power shutdown mode that significantly reduces power dissipation for battery-powered applications.
• Includes TTL/CMOS-compatible inputs with internal pull-up resistors and RS-232 inputs with internal pull-down resistors.
• Provides Schmitt trigger receiver inputs to ensure error-free reception in noisy environments or with slow transition times.

Applications

• Computers
• Peripherals
• Modems
• Printers
• Instruments

Procurement Notes

Verify the specific package variant corresponding to the J suffix against the manufacturer's ordering guide. Confirm the commercial temperature range rating (0°C to 70°C) matches the application requirements. Ensure the datasheet revision aligns with the component batch for accurate pinout and electrical specification validation.

Selection Notes

Select this component when a single 5 V supply is available but standard RS-232 voltage levels are required. The ADM236L is suitable for designs needing four drivers and three receivers with integrated charge pumps. Consider the shutdown feature if power conservation is critical. Verify that the load capacitance does not exceed 2500 pF for optimal slew rate performance.

Part Context

The ADM236L belongs to the ADM2xxL family of line drivers/receivers designed for EIA-232-E and V.28 interfaces. This family serves as an enhanced upgrade to the AD2xx series, offering lower power consumption and faster slew rates. The ADM236L specifically provides a comprehensive interface solution with multiple drivers and receivers in a single package.

Replacement Considerations

The ADM236L is a plug-in upgrade for the MAX223, MAX230 through MAX241, and AD230 through AD241 families. Verify pin compatibility and electrical specifications before substituting these legacy parts.

FAQ

How does the ADM236L generate RS-232 voltages?

It uses two internal charge pump voltage converters. One stage doubles the 5 V input to +10 V, and the second stage inverts this to -10 V, eliminating the need for external dual supplies.

What is the function of the SD pin?

The Shutdown (SD) pin controls the low power mode. When driven high, it disables the charge pump, turns off the drivers, and places receiver outputs in a high impedance state, reducing power dissipation to less than 5 µW.

Are the receiver outputs tri-statable?

Yes, the ADM236L includes an Enable (EN) input. When EN is high, the receiver outputs are disabled and placed in a high impedance state, allowing them to share a common bus with microprocessor systems.