NXP Semiconductors SC16C754BIB80,528

Overview

SC16C754BIB80 from NXP Semiconductors is a quad UART IC with 64-byte transmit/receive FIFOs, hardware/software flow control, and support for data rates up to 5 Mbit/s at 3.3 V or 5 V. It operates across 2.5 V–5 V supply rails, features programmable baud rate generation, and delivers full modem control (RTS/CTS/DSR/DTR/RI/CD) for industrial serial communication systems requiring high-throughput, low-overhead multi-channel RS-232/RS-485 interface bridging.

For engineers reviewing the SC16C754BIB80 datasheet, SC16C754BIB80 pinout, SC16C754BIB80 application, or SC16C754BIB80 equivalent, this device serves as a drop-in upgrade path for legacy TL16C754 and SC16C654IA68 designs-offering enhanced FIFO trigger control, auto-RTS/CTS, and unified RXRDY/TXRDY signaling in an LQFP80 package suitable for space-constrained embedded controllers and industrial gateways.

Technical Context

The SC16C754BIB80 implements four independent UART channels sharing a common 8-bit parallel bus interface, each with dedicated 64-byte FIFOs, programmable trigger levels via TCR and TLR registers, and fully prioritized six-level interrupt architecture. Its clock system supports both crystal (XTAL1/XTAL2) and external clock inputs, with CLKSEL enabling divide-by-1 or divide-by-4 prescaling.

Hardware flow control uses auto-RTS (activated when RX FIFO level falls below halt threshold) and auto-CTS (blocking TX when CTS goes inactive mid-stop-bit), while software flow control supports dual Xon/Xoff character sets with configurable comparison logic and 'Xon Any' resume functionality-all managed through the Enhanced Feature Register (EFR) and Transmission Control Register (TCR).

Key Specifications

Pinout & Package

SC16C754BIB80 is housed in an 80-pin plastic LQFP package (12 × 12 × 1.4 mm, SOT315-1) with exposed thermal pad. Pin functions include four independent UART channel I/Os (TXA–TXD, RXA–RXD), full modem control signals (RTSA–RTSD, CTSA–CTSD, DSRA–DSRD, DTRA–DTRD, RIA–RID, CDA–CDD), parallel bus interface (D0–D7, A0–A2, IOR, IOW, CSA–CSD), and global control pins (RESET, CLKSEL, INTSEL, TXRDY, RXRDY, XTAL1, XTAL2).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL16C754IPM and SC16C654IA68, SC16C754BIB80 delivers higher throughput, finer-grained flow control, and simplified system integration via unified status signaling - making it optimal for new designs targeting industrial IoT edge nodes and multi-protocol gateways.

Availability

SC16C754BIB80 is available at Aetrix Electronics and suitable for industrial automation, embedded communications, and medical instrumentation requiring stable component supply across extended product lifecycles.

Supply support for SC16C754BIB80 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 specializing in secure connectivity solutions for automotive, industrial, and IoT markets, with deep expertise in mixed-signal interface ICs.

The SC16C754B belongs to NXP's high-performance UART product line, engineered specifically for industrial-grade serial communication systems demanding robustness, configurability, and long-term supply stability.

FAQ

What is the maximum data rate supported by SC16C754BIB80?

The SC16C754BIB80 supports up to 5 Mbit/s at 3.3 V or 5 V supply voltages, and up to 3 Mbit/s at 2.5 V. This is achieved using its programmable 16-bit baud rate generator with optional ÷4 prescaler. The actual achievable rate depends on crystal accuracy and system clock stability - typical designs achieve ±0.5% error at 5 Mbit/s with a 25 MHz crystal. SC16C754BIB80 maintains full functionality including FIFO operation and flow control at all supported rates.

Does SC16C754BIB80 support hardware flow control with automatic RTS/CTS management?

Yes, SC16C754BIB80 provides full auto-RTS and auto-CTS functionality controlled via the Enhanced Feature Register (EFR[7:6]). Auto-RTS asserts RTS when the RX FIFO level drops below a user-programmed halt threshold (stored in TCR[3:0]), and de-asserts when the level reaches the resume threshold (TCR[7:4]). Auto-CTS blocks transmission when CTS goes inactive mid-stop-bit. Both features operate independently and eliminate host CPU involvement in flow control decisions. SC16C754BIB80 implements this without external logic.

How does the SC16C754BIB80 handle interrupt prioritization across its four UART channels?

SC16C754BIB80 implements a fully prioritized six-level interrupt system where each channel's events (RX ready, TX empty, line status, modem status, Xoff detection, CTS/RTS change) are assigned fixed priority levels. Interrupts from different channels at the same priority level are resolved by channel ID order (A > B > C > D). The Interrupt Identification Register (IIR) reports pending interrupt type and channel, allowing efficient servicing without polling. SC16C754BIB80 guarantees deterministic response times even under full-load conditions across all four UARTs.

Can SC16C754BIB80 be used with a 2.5 V microcontroller interface?

Yes, SC16C754BIB80 supports true 2.5 V operation for both I/O and core logic, with guaranteed timing and functionality across the full industrial temperature range. Its 5 V-tolerant inputs (D0–D7, A0–A2, IOR, IOW, CSA–CSD, RESET, CLKSEL, INTSEL) allow direct connection to 5 V peripherals without level shifters. When powered at 2.5 V, SC16C754BIB80 maintains 3 Mbit/s max data rate and full register compatibility - making it ideal for mixed-voltage systems such as battery-powered gateways interfacing legacy 5 V sensors.

What is the function of the TXRDY and RXRDY pins on SC16C754BIB80?

TXRDY and RXRDY are active-low, wire-ORed status outputs that reflect the combined state of all four UART channels' transmit and receive FIFOs. TXRDY goes LOW when any TX FIFO has space equal to or greater than its programmed trigger level; RXRDY goes LOW when any RX FIFO contains data at or above its trigger level or experiences a timeout. These signals simplify DMA controller integration by eliminating per-channel handshaking logic. SC16C754BIB80 drives these pins directly - no external logic required.