NXP Semiconductors SC16C754BIA68,512

Overview

SC16C754BIA68 from NXP Semiconductors is a quad UART IC with 64-byte transmit/receive FIFOs, hardware/software flow control, and up to 5 Mbit/s data rate at 3.3 V/5 V operation. It serves as a high-density serial interface controller in industrial communication gateways, embedded modems, and multi-port terminal servers-enabling simultaneous RS-232/RS-485 channel management via a single 8-bit parallel bus.

For engineers reviewing the SC16C754BIA68 datasheet, SC16C754BIA68 pinout, SC16C754BIA68 application, or SC16C754BIA68 equivalent, key selection criteria include its PLCC68 package compatibility, 64-byte FIFO trigger programmability, auto-RTS/CTS implementation, TCR-based flow threshold control, and support for 5/6/7/8-bit character framing with selectable parity and stop bits.

Technical Context

The SC16C754BIA68 implements four independent UART channels sharing a common 8-bit parallel bus, each with dedicated modem control (RTS/CTS/DSR/DTR/RI/CD), interrupt outputs (INTA–INTD), and FIFO-ready signaling (TXRDY/RXRDY). Its architecture integrates a programmable baud rate generator with prescaler (÷1 or ÷4), Transmission Control Register (TCR) for per-channel RX FIFO halt/resume thresholds, and FIFO Ready (FIFO Rdy) register for consolidated TXRDY/RXRDY status read in one access.

It supports full-duplex asynchronous serial communication with false start-bit detection, line-break generation/detection, and complete error reporting-including framing, parity, overrun, and break errors-while maintaining operational status visibility in both normal and Sleep modes. Internal loopback enables on-board diagnostics without external hardware.

Key Specifications

Pinout & Package

SC16C754BIA68 is housed in a plastic leaded chip carrier (PLCC68) package with 68 leads, suitable for through-hole or surface-mount assembly using standard PLCC footprints. The package provides robust thermal performance and mechanical stability in industrial PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SC16C654IA68 and TL16C754IPM, the SC16C754BIA68 delivers superior flow control determinism via TCR-programmed thresholds and higher 5 Mbit/s data rate-making it optimal for real-time industrial serial consolidation where buffer management and timing predictability are critical.

Availability

SC16C754BIA68 is available at Aetrix Electronics and suitable for industrial multi-port terminal servers, embedded modem interfaces, medical diagnostic equipment, and rack-mounted serial console servers requiring stable component supply across extended product lifecycles.

Supply support for SC16C754BIA68 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 deep expertise in interface, power management, and RF technologies.

The SC16C754BIA68 belongs to NXP's legacy industrial UART product line, designed specifically for high-reliability, multi-channel serial communication in harsh environments where long-term availability and pin compatibility with prior-generation devices are essential.

FAQ

What is the maximum data rate supported by the SC16C754BIA68?

The SC16C754BIA68 supports up to 5 Mbit/s at 3.3 V or 5 V supply, and up to 3 Mbit/s at 2.5 V. This rating applies to each of its four UART channels independently. The actual achievable rate depends on crystal accuracy, baud rate divisor settings, and external driver/receiver capabilities. The SC16C754BIA68 achieves this using an integrated prescaler and programmable baud rate generator with 16-bit divisor resolution.

Does the SC16C754BIA68 support hardware flow control, and how is it implemented?

Yes, the SC16C754BIA68 supports hardware flow control via auto-RTS and auto-CTS functions enabled through the Enhanced Feature Register (EFR[7:6]). Auto-RTS asserts RTS when the RX FIFO falls below a TCR-defined halt level and deasserts it upon reaching that level; auto-CTS gates transmission based on CTS input state. These features are fully configurable per channel and eliminate RX FIFO overrun without CPU intervention. The SC16C754BIA68 requires no external logic to implement compliant RTS/CTS handshaking.

How does the SC16C754BIA68 handle interrupt prioritization across its four UART channels?

The SC16C754BIA68 implements six prioritized interrupt levels, with individual INTA–INTD outputs per channel. Interrupt sources-including receiver line status, RX timeout, RHR ready, THR empty, modem status, and Xoff detection-are encoded in the Interrupt Identification Register (IIR) with fixed priority ordering. Higher-priority conditions (e.g., line errors) preempt lower-priority ones (e.g., THR empty), ensuring deterministic response to critical events. The SC16C754BIA68 allows masking per-source via the Interrupt Enable Register (IER) without affecting priority hierarchy.

Can the SC16C754BIA68 operate with different character lengths and parity configurations?

Yes, the SC16C754BIA68 supports programmable serial frame formats: 5-, 6-, 7-, or 8-bit characters; even, odd, or no parity; and 1, 1.5, or 2 stop bits-all configured via the Line Control Register (LCR). Parity generation and detection occur per byte, with error flags reported in the Line Status Register (LSR). These settings apply independently to each UART channel, enabling mixed-protocol operation on a single SC16C754BIA68 device.

What package type is used for the SC16C754BIA68, and what are its key mechanical features?

The SC16C754BIA68 uses a plastic leaded chip carrier (PLCC68) package with 68 leads, conforming to SOT188-2 standard dimensions. It features a square body with J-leads for reliable solder joint formation, rated for −40 °C to +85 °C operation. The PLCC68 footprint supports both through-hole and surface-mount assembly, and includes dedicated pins for CLKSEL and INTSEL not present in LQFP64 variants-enabling prescaler selection and interrupt output control. The SC16C754BIA68's PLCC68 package ensures mechanical robustness in vibration-prone industrial deployments.