NXP Semiconductors SC16C554IB80,528

Overview

SC16C554IB80 from NXP Semiconductors (formerly Philips) is a quad-channel UART IC with 16-byte transmit/receive FIFOs, integrated IrDA encoder/decoder, and dual-mode (Intel 16/ Motorola 68) bus interface. It supports up to 5 Mbit/s serial data rates at 5 V/3.3 V, operates across industrial temperature range (−40 °C to +85 °C), and delivers hardware/software flow control for high-throughput multi-channel serial communication in embedded industrial controllers.

For engineers reviewing the SC16C554IB80 datasheet, SC16C554IB80 pinout, SC16C554IB80 application, or SC16C554IB80 equivalent, key selection criteria include LQFP80 package compatibility, 80-pin 16/68-mode interface configuration, IrDA support, FIFO trigger level programmability, and drop-in replacement capability versus ST16C554 and TL16C554 in legacy designs.

Technical Context

The SC16C554IB80 implements four independent asynchronous serial channels sharing a single 8-bit bidirectional data bus, with register-level access controlled via A0–A2 address lines and mode-selectable strobes (IOR/IOW in 16 mode; R/W and CS in 68 mode). Its internal architecture includes dedicated 16-byte TX/RX FIFOs per channel, programmable baud rate generator with DLL/DLM registers, and enhanced feature register (EFR) enabling auto-RTS/CTS flow control and Xon/Xoff character detection.

It integrates IrDA physical layer encoding/decoding compliant with IrDA 1.0, supports false start-bit detection, line break generation/detection, and full modem control (DSR, DTR, CTS, RTS, RI, CD). Internal diagnostics include loop-back mode and prioritized interrupt system with individual channel status reporting via LSR, MSR, and ISR registers.

Key Specifications

Pinout & Package

LQFP80 package (SOT315-1), 12 mm × 12 mm × 1.4 mm body, 80 leads, exposed thermal pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ST16C554CJ and TL16C554IPN, the SC16C554IB80 uniquely combines LQFP80 mechanical robustness, full industrial temperature rating, dual-bus interface flexibility, and on-die IrDA - making it the only option supporting drop-in replacement in legacy 68-pin designs while enabling new infrared-capable platforms.

Availability

SC16C554IB80 is available at Aetrix Electronics and suitable for industrial PLC gateways, medical multi-port interfaces, retail POS expansion modules, and legacy telecom modernization projects requiring stable component supply and long-term obsolescence management.

Supply support for SC16C554IB80 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, formerly Philips Semiconductors, is a global leader in high-performance mixed-signal ICs for industrial, automotive, and communication systems, with deep expertise in serial interface and connectivity solutions.

The SC16C554IB80 belongs to NXP's legacy UART product line designed specifically for high-reliability embedded systems requiring multi-channel asynchronous serial bridging with enhanced buffering, protocol flexibility, and industrial-grade robustness.

FAQ

What is the maximum serial data rate supported by the SC16C554IB80?

The SC16C554IB80 supports up to 5 Mbit/s at 5 V and 3.3 V supply voltages, and up to 3 Mbit/s at 2.5 V. This performance is achieved using an external clock input; with a 24 MHz crystal, the maximum achievable rate is 1.5 Mbit/s. The SC16C554IB80's baud rate generator uses programmable divisor latch registers (DLL/DLM) to achieve precise fractional division for standard and custom rates.

Does the SC16C554IB80 support both Intel and Motorola bus interfaces?

Yes, the SC16C554IB80 supports dual bus modes via the 16/68 pin (Pin 50). When driven HIGH, it operates in 16-mode (Intel-compatible) with individual chip selects (CSA–CSD) and IOR/IOW strobes. When driven LOW, it switches to 68-mode (Motorola-compatible) using CS, A3, and A4 for channel selection and R/W for combined read/write control - enabling reuse across diverse microprocessor platforms.

How does the SC16C554IB80 handle hardware flow control?

The SC16C554IB80 implements automatic RTS/CTS flow control via its Enhanced Feature Register (EFR). Setting EFR[6] (Auto RTS) and EFR[7] (Auto CTS) enables real-time monitoring of CTS inputs and dynamic assertion of RTS outputs per channel. This eliminates software polling and prevents buffer overflow - for example, TX halts immediately upon CTS deassertion and resumes only after CTS reasserts, ensuring zero data loss under burst traffic.

Can the SC16C554IB80 be used for infrared communication?

Yes, the SC16C554IB80 integrates a full IrDA 1.0-compliant encoder/decoder per UART channel. It accepts standard UART data and generates encoded SIR (Serial Infrared) pulses at 115.2 kbps, while decoding incoming IR signals back to serial data - eliminating the need for external IrDA transceivers and reducing bill-of-materials cost and PCB footprint in handheld or kiosk applications.

What is the purpose of the RXRDY and TXRDY pins on the SC16C554IB80?

RXRDY (Pin 54) and TXRDY (Pin 55) are active-LOW wire-ORed status signals indicating readiness across all four UART channels. RXRDY goes LOW when any receive FIFO contains data (≥1 byte), signaling the CPU to read; TXRDY goes LOW when any transmit FIFO has ≥1 empty location, signaling readiness to write. These simplify interrupt-driven or polled I/O without per-channel status polling.