NXP Semiconductors P89LPC903FD,112

Overview

P89LPC903FD,112 from NXP Semiconductors (formerly Philips) is an 8-bit microcontroller based on a two-clock 80C51 core, delivering six times the instruction throughput of standard 80C51 devices at same frequency. It integrates 1 kB Flash code memory, 128-byte RAM, dual 16-bit timers, a 23-bit system/real-time clock, two analog comparators, and an enhanced UART with fractional baudrate generation - all in an 8-pin SO-8 package for compact embedded control applications including sensor interfaces and low-pin-count industrial controllers.

For engineers reviewing the P89LPC903FD,112 datasheet, P89LPC903FD,112 pinout, P89LPC903FD,112 application, or P89LPC903FD,112 equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative options - supporting rapid selection, schematic integration, and firmware development without external oscillator components or reset circuitry.

Technical Context

The P89LPC903FD,112 executes instructions in two to four clocks using an accelerated 80C51 architecture, enabling 18 MHz operation with 111–222 ns instruction cycles. Its internal RC oscillator is factory-calibrated to ±1 % and fine-tunable via TRIM register, eliminating need for external crystal while supporting UART communication and real-time clock functionality.

It features a dedicated enhanced UART with break detection, framing error handling, automatic address recognition, and versatile interrupt capability - distinct from P89LPC901/902 variants. The device supports up to six I/O pins when using internal oscillator and reset, with Schmitt-triggered inputs, programmable output modes (quasi-bidirectional, open-drain, push-pull), and port pattern-match interrupt on Port 0.

Key Specifications

Pinout & Package

Package: 8-pin SO-8 (SOT96-1), body width 7.5 mm, industry-standard pinout with VDD (pin 1), VSS (pin 8), and RST (pin 4).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with P89LPC902FD,112 and P89LPC901FD,112, the P89LPC903FD,112 uniquely combines UART, dual analog comparators, and internal RC oscillator - making it the only variant capable of self-contained sensor-to-serial communication in minimal 8-pin footprint without external timing components.

Availability

P89LPC903FD,112 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart keypad controllers, low-power remote transmitters, and embedded UART bridges requiring stable component supply across extended product lifecycles.

Supply support for P89LPC903FD,112 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 (originally Philips Semiconductors) is a global leader in high-performance mixed-signal ICs, with expertise in secure connectivity, automotive, and industrial microcontrollers.

The P89LPC90x family was designed for cost-sensitive, space-constrained embedded control applications requiring integrated peripherals, low power, and minimal external components - targeting industrial automation, consumer electronics, and sensor interface markets.

FAQ

What is the maximum operating frequency of the P89LPC903FD,112?

The P89LPC903FD,112 operates at up to 18 MHz when using an external crystal or resonator. With its internal RC oscillator, it supports frequencies from 20 kHz to 18 MHz, factory-calibrated to ±1 % and fine-tunable via the TRIM register. This allows full-speed UART operation and real-time clock accuracy without external timing components - a key advantage of the P89LPC903FD,112 over crystal-dependent variants.

Does the P89LPC903FD,112 support in-system programming (ISP)?

Yes, the P89LPC903FD,112 supports Serial Flash In-Circuit Programming (ICP) using commercial EPROM programmers and In-Application Programming (IAP-Lite) for runtime code updates. Flash security bits prevent unauthorized reading of application code. During power-on, holding RST/P1.5 low forces ISP mode - enabling field firmware upgrades without removing the P89LPC903FD,112 from the PCB.

How many I/O pins are available on the P89LPC903FD,112 in standard configuration?

The P89LPC903FD,112 provides up to six usable I/O pins when configured with internal oscillator and internal reset options. Pins P0.0–P0.6, P1.0–P1.1, and P1.5 are functionally available, though P1.5 is input-only and used for reset. Port configuration registers (P0M1/P0M2/P1M1/P1M2) allow per-pin mode selection - ensuring flexible allocation of the P89LPC903FD,112's limited pin count for mixed analog/digital tasks.

What UART features distinguish the P89LPC903FD,112 from P89LPC901FD,112 and P89LPC902FD,112?

The P89LPC903FD,112 is the only variant in the P89LPC90x family with a fully enhanced UART, featuring fractional baudrate generation, break detection, framing error detection, automatic address recognition, and versatile interrupt capabilities. Neither P89LPC901FD,112 nor P89LPC902FD,112 includes UART hardware - making the P89LPC903FD,112 essential for any design requiring serial communication without external UART ICs.

Can the P89LPC903FD,112 operate without external passive components?

Yes - the P89LPC903FD,112 requires only VDD and VSS connections when using the internal RC oscillator and internal power-on reset. No external crystal, capacitors, or reset IC are needed. Its 5 V tolerant I/O pins further eliminate level-shifter requirements in mixed-voltage systems. This self-contained operation is a defining characteristic of the P89LPC903FD,112 and reduces bill-of-materials cost and board area significantly.