NXP Semiconductors SC16C2550IN40,112

Overview

SC16C2550IN40,112 from NXP Semiconductors (formerly Philips) is a dual-channel UART IC with 16-byte transmit and receive FIFOs, integrated IrDA encoder/decoder, and independent programmable baud rate generators for each channel. It operates at 5 V, 3.3 V, or 2.5 V, supports up to 5 Mbits/s data rates, and is used in industrial serial communication systems requiring high-throughput, low-CPU-overhead data bridging between microcontrollers and modems or RS-232 transceivers.

For engineers reviewing the SC16C2550IN40,112 datasheet, SC16C2550IN40,112 pinout, SC16C2550IN40,112 application, or SC16C2550IN40,112 equivalent, key selection considerations include dual-channel FIFO depth, hardware/software flow control support, DMA-ready TXRDY/RXRDY signaling, IrDA physical layer compatibility, and DIP40 package compatibility with legacy board layouts.

Technical Context

The SC16C2550IN40,112 implements two fully independent UART channels (A and B), each with dedicated 16-byte FIFOs, separate register sets, and individual chip select (CSA/CSB), interrupt (INTA/INTB), and modem control signals (RTS/CTS/DTR/DSR/RI/CD). Its internal architecture includes a shared 16× clock divider with programmable divisor (DLL/DLM), false start-bit detection, and prioritized interrupt logic that distinguishes receiver error, data-ready, transmitter-empty, and modem-status events.

It supports three operational voltage domains (5 V / 3.3 V / 2.5 V), with corresponding maximum data rates of 5 Mbits/s (5 V/3.3 V) and 3 Mbits/s (2.5 V), and integrates an on-chip crystal oscillator (XTAL1/XTAL2) or external clock interface. The device enables both DMA Mode 0 (interrupt-driven per-character) and DMA Mode 1 (block-transfer via TXRDY/RXRDY), with four selectable receive FIFO trigger levels (1/4/8/14 bytes) for optimized throughput in multi-channel environments.

Key Specifications

Pinout & Package

SC16C2550IN40,112 is housed in a plastic dual in-line package (DIP40, SOT129-1) with 40 leads (600 mil width), suitable for through-hole mounting and legacy PCB designs. Pin functions are electrically and mechanically defined per Philips SOT129-1 standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual UART applications.

Compared with ST16C2550, SC16C2550IN40,112 offers identical functionality and pinout but originates from the original Philips design lineage; versus XR16L2550, it lacks enhanced ESD protection and extended temperature rating but maintains full software and hardware compatibility for cost-sensitive legacy upgrades.

Availability

SC16C2550IN40,112 is available at Aetrix Electronics and suitable for industrial PLC gateways, legacy PC expansion cards, IrDA infrared bridges, and multi-protocol modem interfaces requiring stable component supply and long-term obsolescence management.

Supply support for SC16C2550IN40,112 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with roots in Philips' semiconductor division.

The SC16C2550IN40,112 belongs to NXP's legacy UART product line, designed specifically for high-reliability serial communication in industrial control, telecommunications infrastructure, and embedded computing where pin compatibility, FIFO efficiency, and multi-voltage operation are critical.

FAQ

What is the maximum data rate supported by SC16C2550IN40,112?

The SC16C2550IN40,112 supports up to 5 Mbits/s at 5 V or 3.3 V supply, and 3 Mbits/s at 2.5 V. This performance is achieved using an 80 MHz internal clock divider and is validated for reliable operation with standard crystals (e.g., 1.8432 MHz, 7.3728 MHz) or external clock sources. The SC16C2550IN40,112 achieves these rates while maintaining full UART framing integrity including start/stop bits, parity, and error detection.

Does SC16C2550IN40,112 support IrDA physical layer communication?

Yes, SC16C2550IN40,112 integrates a complete IrDA 1.0 encoder/decoder compliant with Serial Infrared (SIR) specifications. It handles baseband modulation/demodulation internally, eliminating the need for external IrDA PHY ICs. The SC16C2550IN40,112 supports standard SIR data rates up to 115.2 kbps and requires only an infrared LED and photodiode on the board for full wireless serial operation.

How does the FIFO architecture in SC16C2550IN40,112 reduce CPU overhead?

The SC16C2550IN40,112 provides 16-byte transmit and receive FIFOs per channel, increasing the time between required CPU interventions from ~93 µs (non-FIFO UART at 115.2 kbps) to >1.53 ms. This allows the host processor to execute other tasks without missing serial data. The SC16C2550IN40,112 further reduces overhead via four programmable RX FIFO trigger levels and DMA-ready TXRDY/RXRDY signals for block-mode transfers.

Is SC16C2550IN40,112 pin-compatible with older UARTs?

Yes, SC16C2550IN40,112 is pin-compatible with ST16C2550 and functionally compatible with ST16C2450 at power-up. It maintains identical DIP40 pinout (SOT129-1), register mapping, and control signal behavior, enabling drop-in replacement in existing designs. The SC16C2550IN40,112 also retains software compatibility with INS8250 and SC16C550 for legacy driver reuse.

What power supply voltages does SC16C2550IN40,112 support?

SC16C2550IN40,112 operates across three voltage domains: 2.5 V, 3.3 V, and 5 V. Each voltage grade defines its own maximum data rate (3 Mbits/s at 2.5 V; 5 Mbits/s at 3.3 V or 5 V) and is fully specified across the industrial temperature range (−40°C to +85°C). The SC16C2550IN40,112 requires no external level shifters when interfacing with CPUs or peripherals operating at any of these rails.