NXP Semiconductors SCC2698BC1A84,512

Overview

SCC2698BC1A84,512 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 programmable data formats (5–8 data bits, odd/even/no parity, 1/1.5/2 stop bits), 26 fixed baud rates up to 115.2 kbaud, and independent receiver/transmitter clocking via internal BRG, four 16-bit counter/timers, or external 1X/16X clocks. 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 SCC2698BC1A84,512 datasheet, SCC2698BC1A84,512 pinout, SCC2698BC1A84,512 application, or SCC2698BC1A84,512 equivalent, key selection considerations include its quadruple-buffered receiver FIFO per channel, RTS/CTS handshaking support, on-chip crystal oscillator, power-down mode with register retention, and 16 multipurpose I/O pins enabling DMA and modem control without external logic.

Technical Context

The SCC2698BC1A84,512 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 dedicated interrupt output (INTRN). Each channel features separate receiver and transmitter clock selectors, allowing asymmetric baud rate configuration - critical for clustered terminal systems where local and remote links operate at different speeds.

Its timing architecture integrates a crystal oscillator (3.6864 MHz typical), a baud rate generator producing 16× clock outputs, and four programmable 16-bit counter/timers usable as baud rate sources, timeout generators, or general-purpose clocks. The receiver uses 16× oversampling for start-bit detection and center-sampling of data bits, while the transmitter includes break generation, automatic echo, and local/remote loopback modes.

Key Specifications

Pinout & Package

SCC2698BC1A84,512 is housed in an 84-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead geometry, designed for surface-mount assembly and thermal reliability in industrial temperature range (0 °C to +70 °C). Pin functions are fully documented in the Philips/NXP datasheet, including dual-purpose I/O capability across 16 MPP/MPO pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SCC2698BC1A84,512, the SCC2692BZ offers fewer channels and reduced feature set, limiting scalability in dense serial gateway applications; the XR16V550 provides larger FIFOs and modern bus interfaces but requires voltage translation and external clocking, increasing design complexity for legacy +5 V industrial systems.

Availability

SCC2698BC1A84,512 is available at Aetrix Electronics and suitable for industrial terminal servers, legacy POS back-end interfaces, and embedded SCADA RTUs requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for SCC2698BC1A84,512 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 heritage in communications ICs from its Philips Semiconductors roots.

The SCC2698BC1A84,512 belongs to NXP's legacy communications interface product line, engineered specifically for high-reliability, multi-port serial infrastructure in industrial control, telecom access equipment, and embedded computing platforms.

FAQ

What is the maximum baud rate supported by the SCC2698BC1A84,512?

The SCC2698BC1A84,512 supports non-standard baud rates up to 115.2 kbaud using its internal baud rate generator. When driven by external 1X or 16X clocks, higher rates are achievable depending on clock source stability and system timing margins. The device's 16× oversampling ensures reliable reception at these speeds, and its quadruple-buffered receiver FIFO helps prevent overrun during high-throughput transfers. All eight channels of the SCC2698BC1A84,512 can operate simultaneously at independent baud rates.

Does the SCC2698BC1A84,512 include an integrated crystal oscillator?

Yes, the SCC2698BC1A84,512 includes an on-chip crystal oscillator circuit compatible with a standard 3.6864 MHz crystal connected between X1/CLK and X2 pins. This oscillator serves as the primary timing reference for the baud rate generator, counter/timers, and internal state machines. If an external clock is preferred, it may be applied to X1/CLK while leaving X2 unconnected. The oscillator remains functional in all operating modes except power-down, where it is frozen to reduce current draw while preserving register contents.

How does hardware flow control work on the SCC2698BC1A84,512?

Hardware flow control on the SCC2698BC1A84,512 is implemented via RTS/CTS signaling using programmable multi-purpose pins. RTSN (Request to Send) is available on MPO pins and can be automatically asserted when the receiver FIFO is not full; CTSN (Clear to Send) is assigned to MPI0 pins and, when enabled via MR2[4], halts transmission immediately upon going high. The SCC2698BC1A84,512 monitors CTSN at the start of each character transmission - if deasserted mid-transmission, the current byte completes normally before pausing further output.

Can the SCC2698BC1A84,512 operate from a 3.3 V supply?

No, the SCC2698BC1A84,512 is specified for single +5 V ±5 % operation only. Its I/O structure, internal logic thresholds, and oscillator circuitry are designed for TTL-compatible voltage levels. Attempting to power the SCC2698BC1A84,512 from 3.3 V will result in improper functionality, including failure of the crystal oscillator, incorrect register reads/writes, and unreliable serial communication. For 3.3 V systems, level-shifting buffers or alternative UARTs such as the EXAR XR16V550 must be used alongside the SCC2698BC1A84,512.

What is the function of the MPP1 and MPP2 pins on the SCC2698BC1A84,512?

The MPP1 and MPP2 pins on the SCC2698BC1A84,512 are programmable multi-purpose I/O pins - eight MPP1 and eight MPP2 pins total - each configurable as input or output via the OPCR register. As inputs, MPP1 accepts transmitter clock (TxCLK) and MPP2 accepts receiver clock (RxCLK); as outputs, they reflect TxRDY and RxRDY/FULL status respectively. These pins include internal pull-up resistors and enable direct connection to RS-485 transceivers or DMA controllers without external components, making them essential for compact, high-integration serial interface designs using the SCC2698BC1A84,512.