Texas Instruments TL16C554IPN

Overview

TL16C554IPN from Texas Instruments is a quadruple UART IC integrating four enhanced TL16C550B asynchronous communications elements (ACEs) with shared steering logic, supporting up to 1-Mbaud serial communication at 16-MHz clock input, 16-byte FIFO buffering per channel, and full modem control (CTS/RTS/DSR/DTR/RI/DCD). It serves as a high-density serial interface controller in industrial PC backplanes, multi-port terminal servers, and legacy RS-232/RS-422 expansion cards.

For engineers reviewing the TL16C554IPN datasheet, TL16C554IPN pinout, TL16C554IPN application, or TL16C554IPN equivalent, this page delivers verified functional identity, validated 80-pin TQFP package mapping, confirmed FIFO-mode interrupt prioritization, exact register-level UART configuration capability, and two rigorously cross-checked alternative parts for multi-channel serial design continuity.

Technical Context

The TL16C554IPN implements four independent UART channels sharing a common 8-bit bidirectional data bus (D7–D0), address decoding (A0–A2), and chip-select architecture (CSA–CSD), each with dedicated transmit/receive FIFOs, programmable baud rate generators (divisor range 1–65535), and full line/modem status reporting. Its dual operating modes-TL16C450-compatible (shift-register) and FIFO mode-are selected via software-controlled FCR bit 0.

Interrupt handling uses a fully prioritized system with individual INTA–INTD outputs per channel plus global INTN control, while modem signaling supports hardware flow control and status change detection (ΔCTS/ΔDSR/ΔDCD/TERI) with precise timing: transmitter interrupt latency ≤32 RCLK cycles, receiver timeout interrupt triggered after ≥4 character times, and RXRDY/TXRDY ready signals synchronized to internal RCLK.

Key Specifications

Pinout & Package

TL16C554IPN is housed in an 80-pin Thin Quad Flat Package (TQFP, PN package), with 0.5-mm lead pitch, exposed thermal pad (not electrically connected), and RoHS-compliant finish. Pin functions are defined per TI SLLS165G datasheet revision March 2006.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL16C554IPN, XR16L788IQ-F offers larger FIFOs and integrated regulation but requires driver updates, while XR16M554IL58-F adds PCIe/USB bridging and wider voltage support at the cost of legacy bus compatibility - making TL16C554IPN the optimal choice for register-identical upgrades in established 5-V parallel-bus systems.

Availability

TL16C554IPN is available at Aetrix Electronics and suitable for industrial terminal servers, legacy PC expansion cards, and medical data loggers requiring stable component supply across extended product lifecycles.

Supply support for TL16C554IPN 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity solutions, with decades of heritage in industrial-grade interface ICs.

The TL16C554IPN belongs to TI's legacy asynchronous communications element (ACE) product line, engineered specifically for high-reliability, multi-port serial I/O in industrial computing, telecommunications infrastructure, and embedded control systems.

FAQ

What is the maximum supported baud rate for TL16C554IPN?

The TL16C554IPN supports up to 1 Mbit/s baud rate when operated with a 16-MHz input clock and 16× oversampling. This is achieved using its programmable 16-bit baud rate generator (DLL/DLM), which divides the reference clock by any integer from 1 to 65,535. The actual achievable rate depends on clock accuracy and line conditions, but the device guarantees specification compliance up to 1 Mbps per channel under recommended operating conditions (VCC = 4.75–5.25 V, TA = −40°C to +85°C).

Does TL16C554IPN support both FIFO and legacy TL16C450 modes?

Yes, TL16C554IPN supports two mutually exclusive operational modes controlled by bit 0 of the FIFO Control Register (FCR). When FCR0 = 1, it operates in enhanced FIFO mode with 16-byte buffers per channel and trigger-level interrupts. When FCR0 = 0, it reverts to TL16C450 mode using shift registers only - preserving full register-level compatibility with legacy drivers and BIOS implementations while disabling FIFO functionality.

What package type and pin count does TL16C554IPN use?

TL16C554IPN is packaged in an 80-pin Thin Quad Flat Package (TQFP) with PN suffix, measuring 12 mm × 12 mm and featuring 0.5-mm lead pitch. This package is distinct from the 68-pin PLCC (FN) variant and includes dedicated pins for all four UART channels (TXA–TXD, RXA–RXD), modem signals (RTS/CTS/DSR/DTR/RI/DCD), and shared bus interface (D0–D7, A0–A2, IOR/IOW, CSA–CSD).

How does TL16C554IPN handle interrupt prioritization across four channels?

TL16C554IPN implements a fixed-priority interrupt architecture where INTA has highest priority and INTD lowest. Each channel asserts its own interrupt output (INTA–INTD), and the global INTN pin controls whether interrupts are enabled via MCR bit 3 (OUT2). Within each channel, receiver line status (e.g., framing/parity errors) takes precedence over receive data available, which in turn ranks above transmitter holding register empty - ensuring critical error conditions are serviced first.

Is TL16C554IPN compatible with standard PC BIOS and DOS drivers?

Yes, TL16C554IPN maintains full register-level compatibility with the industry-standard TL16C550B UART, including identical memory-mapped register addresses (e.g., base + 0–7), bit definitions (LCR, IER, FCR), and interrupt behavior. This allows seamless integration with legacy x86 BIOS, DOS device drivers (e.g., ANSI.SYS), and Windows NT/XP serial port stacks without modification - provided the host system decodes chip selects (CSA–CSD) and address lines (A0–A2) per TI's recommended interface schematic.