NXP Semiconductors SCC2698BC1A84,518

Overview

SCC2698BC1A84 from NXP Semiconductors (formerly Philips) is an enhanced octal UART IC providing eight independent full-duplex asynchronous serial channels in a single 84-pin PLCC package. It supports up to 115.2 kbaud, quadruple-buffered receivers per channel, programmable data formats (5–8 bits, 1/1.5/2 stop bits, odd/even/no parity), and independent receiver/transmitter baud rate selection via 26 fixed rates or user-defined counter/timer outputs. It is used in industrial terminal servers, multi-port serial concentrators, and legacy embedded communication gateways requiring high channel density and TTL-compatible +5 V operation.

For engineers reviewing the SCC2698BC1A84 datasheet, SCC2698BC1A84 pinout, SCC2698BC1A84 application, or SCC2698BC1A84 equivalent, key selection considerations include its 8-channel full-duplex capability, 3-character receiver FIFO per channel, 16-bit counter/timer per DUART block, multipurpose I/O pin flexibility (MPO/MPP/MPI), and support for RTS/CTS handshaking and break detection - all critical for deterministic serial infrastructure design.

Technical Context

The SCC2698BC1A84 implements four independent DUART blocks (A–D), each containing two UART channels (e.g., Block A = channels a/b), sharing one 16-bit counter/timer and interrupt output (INTRN). Each channel features separate clock select registers (CSR), mode registers (MR1/MR2), and status/command logic, enabling fully independent configuration of data format, baud rate source (BRG, timer, or external 1X/16X), and flow control.

Its timing architecture integrates an on-chip crystal oscillator (3.6864 MHz typical), a 26-rate baud rate generator (BRG) with 16X output, and four programmable 16-bit counter/timers supporting timer, counter, and timeout modes. Baud rate selection is decoupled per channel: receiver and transmitter may use different clock sources - e.g., receiver from BRG, transmitter from timer - enabling dual-speed operation essential for clustered terminal systems.

Key Specifications

Pinout & Package

SCC2698BC1A84 is housed in an 84-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead geometry, designed for reflow soldering and compatible with standard PLCC sockets. Pin 1 is located at the index corner; leads are numbered counterclockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SCC2692B and MAX3100, the SCC2698BC1A84 uniquely delivers 8-channel integration with per-channel FIFO status visibility, dual-speed clocking, and hardware modem control in a single PLCC package - making it irreplaceable in retrofitting legacy multi-port serial infrastructure without board-level changes.

Availability

SCC2698BC1A84 is available at Aetrix Electronics and suitable for industrial terminal servers, legacy protocol gateways, multi-port serial concentrators, and embedded modem control units requiring stable component supply across extended product lifecycles.

Supply support for SCC2698BC1A84 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. Formerly Philips Semiconductors, it maintains extensive legacy product support including the SCC family.

The SCC2698B belongs to NXP's legacy communications IC portfolio, designed specifically for high-reliability, multi-channel asynchronous serial infrastructure in industrial control, telecom access equipment, and mainframe terminal environments.

FAQ

What is the maximum supported baud rate for SCC2698BC1A84?

The SCC2698BC1A84 supports a maximum baud rate of 115.2 kbaud. This is achieved using non-standard BRG rates or user-defined counter/timer outputs. The device's 16X clock architecture ensures accurate sampling at this rate, and its quadruple-buffered receiver minimizes overrun risk even under sustained high-speed traffic. All eight channels of the SCC2698BC1A84 can operate simultaneously at this rate when driven by appropriate clock sources.

Does SCC2698BC1A84 support hardware flow control?

Yes, the SCC2698BC1A84 supports full hardware RTS/CTS flow control per channel. The CTSN input is implemented on MPI0 pins, and RTSN output is available on MPO pins - both configurable via mode register MR2. When enabled, the transmitter automatically pauses transmission if CTSN goes high, resuming only after CTSN returns low. This behavior is handled entirely in hardware, eliminating CPU intervention and ensuring deterministic response in real-time serial systems using the SCC2698BC1A84.

How many interrupt outputs does SCC2698BC1A84 provide, and how are they assigned?

The SCC2698BC1A84 provides four active-low open-drain interrupt outputs: INTRAN, INTRBN, INTRCN, and INTRDN. Each serves two UART channels - INTRAN covers channels a/b, INTRBN covers c/d, INTRCN covers e/f, and INTRDN covers g/h. Each output aggregates eight maskable interrupt conditions (e.g., TxRDY, RxRDY/FFULL, break, CTS change). This architecture allows efficient interrupt handling in host systems without requiring one IRQ per channel, a key design advantage of the SCC2698BC1A84.

Can SCC2698BC1A84 generate RS-485 bus turnaround signals automatically?

Yes, the SCC2698BC1A84 supports automatic RS-485 half-duplex bus control via MR2[5]. When enabled, the RTSN output (on MPO pins) is asserted before transmission begins and deasserted after the final stop bit is sent. This eliminates timing-critical software delays and ensures clean driver enable/disable transitions - critical for avoiding bus contention in multi-drop RS-485 networks. This feature is unique to the SCC2698B family and is fully implemented in the SCC2698BC1A84 PLCC variant.

What is the receiver FIFO depth per channel in SCC2698BC1A84?

The SCC2698BC1A84 implements a 3-character deep First-In-First-Out (FIFO) buffer for each of its eight receiver channels. In addition to the standard RxRDY flag, it provides a dedicated FFULL (FIFO full) status bit accessible via MPO or MPP2 pins. This dual-status signaling allows host firmware or DMA controllers to initiate reads before overflow occurs - significantly reducing interrupt frequency and CPU overhead compared to single-character buffering. The FIFO is integral to the SCC2698BC1A84's quadruple-buffered receiver architecture.