NXP Semiconductors P89LPC931FDH,112

Overview

P89LPC931FDH,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 18 MHz. It integrates 8 kB Flash code memory, 256-byte RAM, dual 16-bit timers, real-time clock, two analog comparators, enhanced UART with fractional baud rate generator, I²C and SPI interfaces, and 23+ configurable I/O pins in a TSSOP28 package - deployed in industrial control panels requiring compact, low-power embedded logic with keypad scanning and sensor monitoring.

For engineers reviewing the P89LPC931FDH,112 datasheet, P89LPC931FDH,112 pinout, P89LPC931FDH,112 application, or P89LPC931FDH,112 equivalent, key selection criteria include Flash size (8 kB vs. 4 kB in P89LPC930FDH), RC oscillator trim capability (±1 % factory calibration), 5 V-tolerant I/Os, and in-application Flash programming support for field firmware updates.

Technical Context

The P89LPC931FDH,112 executes instructions in two to four CPU clocks (vs. 12 in legacy 80C51), enabled by its accelerated two-clock architecture and internal DIVM divider. Its clock system supports four selectable sources: on-chip RC oscillator (7.373 MHz ±1 %, trimmable), Watchdog oscillator (400 kHz), external crystal (20 kHz–18 MHz), or external clock input - all configurable via Flash configuration bits.

Peripheral integration includes dual 16-bit counter/timers (configurable as PWM or port toggle outputs), real-time clock usable as system timer, two analog comparators with programmable reference and inputs, and three serial interfaces (UART with break detection, 400 kHz I²C, full-duplex SPI) - all sharing a unified interrupt controller with four priority levels and eight keypad interrupt inputs.

Key Specifications

Pinout & Package

Package: TSSOP28 (SOT361-1), plastic thin shrink small outline package with 28 leads and 4.4 mm body width.

Key Features

Applications

Equivalent & Alternatives

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

Compared with P89LPC930FDH and LPC921, the P89LPC931FDH,112 offers double the Flash capacity for feature-rich firmware while maintaining full pin and peripheral compatibility with the P89LPC930FDH family - making it the optimal upgrade path for designs needing expanded code space without layout changes.

Availability

P89LPC931FDH,112 is available at Aetrix Electronics and suitable for industrial control panels, smart sensor nodes, energy meter interfaces, and embedded appliance controllers requiring stable component supply across extended product lifecycles.

Supply support for P89LPC931FDH,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 is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications.

The P89LPC931FDH,112 belongs to NXP's legacy LPC900 family of enhanced 80C51 microcontrollers, designed specifically for cost-sensitive, space-constrained embedded systems demanding high integration, low power, and minimal external components.

FAQ

What is the maximum operating frequency of the P89LPC931FDH,112?

The P89LPC931FDH,112 supports a maximum CPU clock frequency of 18 MHz. This is achievable using the high-speed external crystal oscillator option (4–18 MHz range). When operating above 12 MHz, the reset input function on P1.5 must be enabled, and an external power-up reset circuit is required to ensure reliable initialization before VDD reaches specification.

Does the P89LPC931FDH,112 support in-system programming?

Yes, the P89LPC931FDH,112 supports serial Flash programming for in-circuit production coding and In-Application Programming (IAP) of Flash memory. This allows firmware updates to be performed while the device is running in the target system, enabling field upgrades without requiring physical reprogramming equipment.

How many I/O pins does the P89LPC931FDH,112 provide in the TSSOP28 package?

The P89LPC931FDH,112 provides a minimum of 23 configurable I/O pins in the TSSOP28 package. When using on-chip oscillator and reset options, up to 26 I/O pins are available - including Port 0 (8 pins), Port 1 (8 pins), Port 2 (8 pins), and Port 3 (2 pins), with certain pins multiplexed for peripheral functions.

What oscillator options are available for the P89LPC931FDH,112?

The P89LPC931FDH,112 supports four oscillator sources: on-chip RC oscillator (factory-trimmed to 7.373 MHz ±1 %), on-chip Watchdog oscillator (400 kHz), external crystal/resonator (20 kHz–18 MHz), or external clock input on XTAL1. Selection is configured via Flash configuration bits and requires no external components for RC or WDT modes.

Is the P89LPC931FDH,112 pin-compatible with the P89LPC930FDH?

Yes, the P89LPC931FDH,112 is fully pin-compatible and functionally identical to the P89LPC930FDH except for Flash memory size (8 kB vs. 4 kB). Both share the same TSSOP28 package, identical pinout, peripheral set, register map, and electrical specifications - enabling direct substitution where additional code storage is required.