SCC2681AE1A44,518

UARTs (Universal Asynchronous Receiver Transmitter) Overview

The NXP SCC2681AE1A44,518 is a dual asynchronous receiver/transmitter (DUART) manufactured in a CMOS process. It provides two independent full-duplex channels within a single package, designed for direct microprocessor interfacing in polled or interrupt-driven systems. The device supports programmable data formats including 5 to 8 data bits with selectable parity and stop bits. Each channel features quadruple buffered receiver registers to minimize overrun risks. Baud rates are selectable from 22 fixed options ranging from 50 to 115.2 k baud, or derived from an internal 16-bit counter/timer or external clock sources. The component operates on a single +5 V supply and is housed in a 44-pin PLCC package.

UARTs (Universal Asynchronous Receiver Transmitter) Feature Summary

• Dual full-duplex asynchronous communication channels with independent programming capabilities
• Quadruple buffered receiver data registers to reduce interrupt overhead and prevent overrun
• Integrated multipurpose 7-bit input port and 8-bit output port with configurable functions
• Versatile interrupt system featuring a single maskable output and multiple wire-ORable status signals

UARTs (Universal Asynchronous Receiver Transmitter) Applications

• Clustered terminal systems requiring dual-speed channel operations
• Polled or interrupt-driven microprocessor communication interfaces
• Multidrop applications utilizing automatic wake-up modes

UARTs (Universal Asynchronous Receiver Transmitter) Procurement Notes

Verify the specific suffix

UARTs (Universal Asynchronous Receiver Transmitter) Selection Notes

Select this component when designing systems requiring two independent asynchronous serial ports with high buffering depth. Ensure the application utilizes a standard +5V logic environment compatible with the specified voltage limits. Consider the PLCC package constraints if surface mount assembly is required for the target hardware design.

UARTs (Universal Asynchronous Receiver Transmitter) Part Context

This part belongs to the SCC2681 family of dual universal asynchronous receiver/transmitters produced by Philips/NXP Semiconductors. It serves as a legacy interface solution for embedded systems needing robust serial communication capabilities without complex FIFO management. The device supersedes earlier discrete UART implementations by integrating timing generation and I/O expansion into a single MOS-LSI chip.

UARTs (Universal Asynchronous Receiver Transmitter) Replacement Considerations

Public documentation identifies the SCN2681 as the functional predecessor. Direct replacement requires verifying pin compatibility between the DIP and PLCC variants, as package footprints differ significantly across the product family.