NXP Semiconductors SC16C654BIA68,518

Overview

SC16C654BIA68 from NXP Semiconductors (formerly Philips) is a quad UART IC designed for high-throughput serial communication in industrial embedded systems. It supports 5 V, 3.3 V, and 2.5 V operation, delivers up to 5 Mbit/s data rate at 5 V/3.3 V, integrates 64-byte transmit and receive FIFOs per channel, and provides selectable Intel (16-mode) or Motorola (68-mode) bus interface - used in multi-port terminal servers and industrial PLC backplanes.

For engineers reviewing the SC16C654BIA68 datasheet, SC16C654BIA68 pinout, SC16C654BIA68 application, or SC16C654BIA68 equivalent, key selection criteria include quad-channel asynchronous serial support, 64-byte FIFO depth, dual-bus interface flexibility, IrDA encoder/decoder capability, and industrial temperature range (−40 °C to +85 °C) compliance.

Technical Context

The SC16C654BIA68 implements four independent UART channels with fully programmable character formatting (5–8 data bits, 1/1.5/2 stop bits, even/odd/no parity), false start-bit detection, and complete status reporting via line, transmitter, receiver, and modem status registers. Its clock architecture supports crystal (up to 24 MHz) or external clock input, enabling baud rates from DC to 5 Mbit/s (3 Mbit/s at 2.5 V).

It features automatic hardware flow control (RTS/CTS) and software flow control (Xon/Xoff), programmable Xon/Xoff characters, four selectable FIFO trigger levels, and DMA-ready TXRDY/RXRDY signals - though TXRDY and RXRDY are excluded in HVQFN48 packages and not present on this PLCC68 variant per datasheet Fig 3/4 and Table 2.

Key Specifications

Pinout & Package

SC16C654BIA68 uses a plastic leaded chip carrier (PLCC68) package with 68 leads (SOT188-2), 24.2 mm × 24.2 mm body, and J-lead profile suitable for through-hole or surface-mount reflow assembly. Pin functions differ between 16-mode and 68-mode configurations; this device defaults to 16-mode when 16/68 = HIGH.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ST16C654CJ68 and TL16C754BPTR, SC16C654BIA68 uniquely combines triple-voltage operation, IrDA, industrial temp range, and PLCC68 packaging - making it the only option for retrofitting legacy 5 V systems requiring infrared serviceability and thermal robustness.

Availability

SC16C654BIA68 is available at Aetrix Electronics and suitable for industrial terminal servers, PLC backplanes, medical diagnostic equipment, and ruggedized point-of-sale terminals requiring stable component supply across extended product lifecycles.

Supply support for SC16C654BIA68 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 applications.

The SC16C654BIA68 belongs to NXP's legacy high-performance UART product line, engineered specifically for industrial-grade serial infrastructure requiring reliability, multi-voltage flexibility, and long-term availability in harsh environments.

FAQ

What is the maximum data rate supported by the SC16C654BIA68?

The SC16C654BIA68 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 SC16C654BIA68 maintains full functionality including 64-byte FIFO operation and hardware flow control across all supported data rates.

Does the SC16C654BIA68 support both Intel and Motorola bus interfaces?

Yes, the SC16C654BIA68 supports both interfaces via the 16/68 pin: logic HIGH configures 16-mode (Intel-style IOR/IOW/INTA–INTD), while logic LOW configures 68-mode (Motorola-style R/W/IRQ). This dual-mode capability is confirmed in the PLCC68 pin diagrams (Figs 3 and 4) and functional description section of the datasheet. The SC16C654BIA68 powers up functionally equivalent to the 16C454 in 16-mode or 68C454 in 68-mode.

Are TXRDY and RXRDY signals available on the SC16C654BIA68?

Yes, TXRDY and RXRDY signals are available on the SC16C654BIA68. These active-LOW outputs provide wire-ORed status of all four transmit and receive FIFOs respectively, and are explicitly documented for the PLCC68 package in Figures 3 and 4 and Table 2 of the datasheet. They are absent only in HVQFN48 and LFBGA64 packages - not applicable to SC16C654BIA68.

What is the FIFO depth per channel in the SC16C654BIA68?

The SC16C654BIA68 provides 64 bytes of transmit FIFO and 64 bytes of receive FIFO per channel. This is double the capacity of the ST16C654 and quadruple that of the ST16C554. The receive FIFO includes error flags for framing, parity, and overrun errors - directly accessible via the Line Status Register (LSR) and Enhanced Feature Register (EFR).

Does the SC16C654BIA68 include infrared (IrDA) functionality?

Yes, the SC16C654BIA68 integrates a compliant IrDA encoder/decoder supporting SIR (Serial Infrared) at 115.2 kbit/s. This is implemented entirely within the die - no external components required. The feature is enabled via the Enhanced Feature Register (EFR) and operates alongside standard UART functions without performance penalty.