MAX239CNG+

Overview

The MAX239CNG+ is a +5V-powered, multichannel RS-232 line driver and receiver manufactured by Analog Devices Inc./Maxim Integrated. It operates within the MAX220–MAX249 family and supports EIA/TIA-232E and V.28/V.24 communication interfaces. The device features an integrated charge pump that eliminates the need for external bipolar ±12V supplies, enabling single-supply operation from a +5V source. It provides three drivers and five receivers with full-duplex capability. The component is housed in a 24-pin SOIC package and is rated for commercial operating temperatures ranging from 0°C to +70°C.

Feature Summary

• Integrated charge pump circuitry generates internal voltage levels, removing the requirement for external bipolar power supplies.
• Enables single +5V supply operation while maintaining standard RS-232 signal voltage swings.
• Provides multiple independent transmitter and receiver channels for complex serial communication topologies.

Applications

• Interface translation between TTL/CMOS logic and RS-232 standards
• Multidrop RS-232 network implementations
• Portable diagnostics equipment requiring compact form factors

Procurement Notes

Verify the specific suffix 'CNG+' against the manufacturer's current ordering information table to confirm the exact package type (SOIC) and temperature grade (Commercial). Ensure the datasheet revision matches the required specifications, as pin configurations and electrical characteristics can vary across different revisions of the MAX220-MAX249 family documentation.

Selection Notes

Select this component when designing systems that require multiple RS-232 channels but are constrained to a single +5V power rail. It is suitable for applications where board space is limited due to the elimination of external charge-pump capacitors found in older generations. Confirm that the data rate requirements do not exceed the specified limits for the selected load conditions.

Part Context

This part belongs to the MAX220–MAX249 family of +5V-powered multichannel RS-232 drivers and receivers. This series was designed to simplify interface design by integrating charge pumps directly into the IC. The MAX239 variant specifically offers a configuration of three drivers and five receivers, providing flexibility for asymmetric communication needs compared to standard dual-driver parts.

Replacement Considerations

Direct replacements within the same family include other MAX2xx variants with matching channel counts or pin-compatible packages. Verify that any substitute maintains the same SOIC-24 footprint and commercial temperature range if environmental constraints are strict.