NXP Semiconductors SC16C2552IA44,518

Overview

SC16C2552IA44,518 from NXP Semiconductors (formerly Philips) is a dual-channel UART IC designed for high-throughput serial communication in embedded industrial systems. It delivers 16-byte transmit and receive FIFOs, supports up to 5 Mbits/s at 5 V, operates across 2.5 V/3.3 V/5 V supply rails, and features independent programmable baud rate generators per channel. It is used in multi-serial-port industrial controllers requiring reliable modem control and DMA-capable data transfer.

For engineers reviewing the SC16C2552IA44,518 datasheet, SC16C2552IA44,518 pinout, SC16C2552IA44,518 application, or SC16C2552IA44,518 equivalent, key selection criteria include FIFO depth matching, PLCC44 package compatibility, dual-channel interrupt handling (INTA/INTB), TXRDY/RXRDY DMA signaling, and support for RTS/CTS/DSR/DTR/RI/CD modem handshaking in harsh environments.

Technical Context

The SC16C2552IA44,518 implements two fully independent UART channels (A and B), each with dedicated 16-byte FIFOs, separate baud rate generators, and individual interrupt outputs (INTA/INTB). Its register architecture supports concurrent writes to both channel register sets via CHSEL override and AFR[0], enabling synchronized initialization without software arbitration.

It integrates full modem control logic (RTS/CTS/DTR/DSR/RI/CD), internal loop-back diagnostics, and DMA-ready status signals (TXRDYA/TXRDYB, RXRDYA/RXRDYB) tied directly to FIFO trigger levels. The device accepts either crystal (XTAL1/XTAL2) or external clock input up to 80 MHz to achieve 5 Mbits/s operation at 5 V.

Key Specifications

Pinout & Package

SC16C2552IA44,518 is housed in a 44-pin plastic leaded chip carrier (PLCC44, SOT187-2) with J-lead configuration, suitable for through-hole or surface-mount assembly. Pin 1 is located at the index corner adjacent to the notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ST16C2552CJ44 and XR16L2552IL44-F, the SC16C2552IA44,518 uniquely combines triple-voltage operation (2.5/3.3/5 V), industrial temperature range, and concurrent register write capability - making it optimal for legacy-compatible upgrades in ruggedized embedded platforms.

Availability

SC16C2552IA44,518 is available at Aetrix Electronics and suitable for industrial PLC gateways, medical telemetry interfaces, telecom modem cards, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for SC16C2552IA44,518 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. Formerly Philips Semiconductors, it maintains extensive legacy product support and industrial qualification rigor.

The SC16C2552IA44,518 belongs to NXP's industrial communications interface portfolio, designed specifically to replace aging 16C450/16C550 UARTs while delivering higher throughput, lower CPU overhead, and seamless integration into existing 8-bit parallel bus architectures.

FAQ

What voltage levels does the SC16C2552IA44,518 support, and how does that affect system design?

The SC16C2552IA44,518 operates at 2.5 V, 3.3 V, and 5 V supply rails - a rare triple-voltage capability among dual UARTs. This allows direct integration into mixed-voltage industrial backplanes without level shifters. For example, a 3.3 V microcontroller can drive the SC16C2552IA44,518's D0–D7 bus while powering RS-232 transceivers from a separate 5 V rail, simplifying power architecture and reducing BOM cost.

How does the SC16C2552IA44,518 handle interrupt management for two independent UART channels?

The SC16C2552IA44,518 provides physically separate INTA and INTB outputs, each with its own priority-encoded interrupt status register (ISR). This eliminates software arbitration between channels: a microcontroller can service INTA for UART A's receive overflow while deferring INTB for UART B's modem status change. The LSR and MSR registers further isolate error and control status per channel, enabling deterministic real-time response in safety-critical systems.

Can the SC16C2552IA44,518 be used with modern microcontrollers lacking legacy parallel buses?

Yes - while the SC16C2552IA44,518 uses an 8-bit parallel interface (D0–D7, IOR/IOW, A0–A2), it can interface with modern ARM or RISC-V MCUs via GPIO bit-banging or dedicated parallel-to-SPI bridge ICs like the MAX3100. Its register map and timing are fully documented, and the CHSEL/CS decode logic remains compatible with FPGA-based bus wrappers, preserving investment in proven UART firmware stacks.

What is the purpose of the MFA and MFB pins on the SC16C2552IA44,518, and how are they configured?

MFA and MFB are multi-function output pins configurable via bits 1–2 of the Alternate Function Register (AFR). They can be set to OP2 (interrupt enable flag), BAUDOUT (16× baud rate clock output), or RXRDY (FIFO-ready indicator). This flexibility allows designers to monitor DMA readiness without consuming additional GPIOs or route precise clock signals for synchronous peripheral interfacing - all without altering the PLCC44 pin count.

Does the SC16C2552IA44,518 support automatic hardware flow control, and how is it implemented?

The SC16C2552IA44,518 provides full discrete hardware flow control via RTS/CTS signals per channel but does not implement auto-flow control (e.g., XON/XOFF or automatic RTS assertion based on FIFO level). Flow control is managed by external logic or host software reading LSR and MSR bits and toggling MCR[1] (RTS) and checking MSR[4] (CTS). This gives designers deterministic control over handshaking timing - critical in deterministic industrial networks where jitter must be minimized.