NXP Semiconductors SC16C654DBIB64,157

Overview

SC16C654DBIB64 from NXP Semiconductors (formerly Philips) is a quad UART IC designed for high-throughput serial communication in embedded systems. It supports 5 Mbit/s data rates at 3.3 V/5 V, features 64-byte transmit and receive FIFOs per channel, and provides Intel- or Motorola-compatible bus interfaces. It is used in industrial gateways, multi-port RS-232/RS-485 adapters, and telecom infrastructure requiring reliable asynchronous data bridging.

For engineers reviewing the SC16C654DBIB64 datasheet, SC16C654DBIB64 pinout, SC16C654DBIB64 application, or SC16C654DBIB64 equivalent, key selection criteria include its LQFP64 package with 64-pin 10×10 mm footprint, 4-channel independent interrupt support (INTA–INTD), hardware/software flow control (RTS/CTS & Xon/Xoff), IrDA encoder/decoder capability, and compatibility with ST16C654D and TL16C754 in system-level designs.

Technical Context

The SC16C654DBIB64 implements four independent UART channels sharing a common 8-bit bidirectional data bus (D0–D7), address decoding (A0–A2), and chip-select logic (CSA–CSD). Each channel includes dedicated modem control pins (RTS/CTS/DSR/DTR/RI/CD), full status reporting, and programmable character formatting (5–8 data bits, 1–2 stop bits, parity options).

It operates in 16-mode only (Intel interface) on the LQFP64 package, with IOR/IOW strobes, individual INTA–INTD outputs, and no IRQ or R/W pin - confirming fixed 16-bit bus alignment. The internal baud rate generator supports DC to 5 Mbit/s, and FIFO trigger levels are software-selectable across four thresholds to optimize CPU servicing intervals.

Key Specifications

Pinout & Package

SC16C654DBIB64 is housed in a plastic low-profile quad flat package (LQFP64) with 64 leads, 10 × 10 × 1.4 mm body size (SOT314-2), lead pitch of 0.5 mm, and exposed thermal pad for enhanced power dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ST16C654D, SC16C654DBIB64 offers factory-configured continuous-interrupt mode (INTSEL bonded to VCC), simplifying layout; versus TL16C754B, it adds integrated IrDA and lower-power sleep, enabling compact, certified medical and portable diagnostic designs.

Availability

SC16C654DBIB64 is available at Aetrix Electronics and suitable for industrial multi-port serial servers, telecom line card interfaces, embedded test equipment controllers, and medical device communication hubs requiring stable component supply and long-term obsolescence planning.

Supply support for SC16C654DBIB64 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 automotive, industrial, and communication markets.

The SC16C654DBIB64 belongs to NXP's legacy high-performance UART product line, engineered for demanding multi-channel serial infrastructure where reliability, FIFO depth, and interface flexibility are critical.

FAQ

What voltage levels does the SC16C654DBIB64 support?

The SC16C654DBIB64 supports operation at 2.5 V, 3.3 V, and 5 V supply voltages. At 2.5 V, maximum data rate is 3 Mbit/s; at 3.3 V and 5 V, it achieves up to 5 Mbit/s. All I/O pins are 5 V tolerant, allowing safe interfacing with legacy 5 V logic even when the core runs at 3.3 V or 2.5 V. This flexibility makes SC16C654DBIB64 suitable for mixed-voltage board designs without level-shifting circuitry.

Does the SC16C654DBIB64 support both Intel and Motorola bus interfaces?

No - the SC16C654DBIB64 is configured exclusively for the 16-mode (Intel) interface. Its LQFP64 package omits pins required for 68-mode operation (e.g., A3/A4, R/W, IRQ), and includes IOR/IOW, CSA–CSD, and individual INTA–INTD outputs. The 16/68 pin is absent, confirming fixed 16-mode functionality. This differs from the PLCC68 variant, which supports mode selection. SC16C654DBIB64 is therefore optimized for Intel-compatible microcontrollers and x86-based industrial hosts.

How does the SC16C654DBIB64 handle interrupt generation across four UART channels?

The SC16C654DBIB64 provides four dedicated active-HIGH interrupt outputs - INTA, INTB, INTC, and INTD - one per UART channel. Each is independently controlled by the Modem Control Register (MCR[3]) and Interrupt Enable Register (IER). Unlike shared-IRQ architectures, this eliminates interrupt masking conflicts and enables true parallel servicing. SC16C654DBIB64 also supports continuous-interrupt mode (INTSEL internally bonded to VCC), ensuring immediate notification without software-controlled enable/disable sequencing.

What is the role of the CLKSEL pin on the SC16C654DBIB64?

The SC16C654DBIB64 does not include a CLKSEL pin. That pin is present only on the PLCC68 package (e.g., SC16C654BIA68) to select 1× or 4× pre-scaling for the baud rate generator. In the LQFP64 variant, CLKSEL functionality is replaced by MCR[7], which can override the default scaling factor after reset. This simplifies PCB layout for SC16C654DBIB64 while retaining full baud rate programmability - including support for standard rates up to 5 Mbit/s and custom values via divisor latch programming.

Can the SC16C654DBIB64 be used for infrared communication?

Yes - the SC16C654DBIB64 integrates a compliant IrDA 1.0 encoder/decoder. It performs pulse shaping, NRZ encoding, and RZI decoding directly, supporting SIR (Serial Infrared) at 115.2 kbit/s. No external IR transceiver IC is needed; only an IR LED and photodiode (with driver/receiver circuitry) must be added. This capability is confirmed in the official datasheet Rev. 02 and applies specifically to SC16C654DBIB64, enabling compact, certified medical and portable diagnostic designs with wireless configuration and diagnostics.