NXP Semiconductors P89LPC902FD,112

Overview

P89LPC902FD,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 the same frequency. It integrates 1 kB Flash code memory, 128-byte RAM, dual 16-bit timers, a 23-bit system/real-time clock, and two analog comparators - all in an 8-pin SO-8 package. It targets low-cost embedded control applications requiring compact size, low power, and integrated analog sensing.

For engineers reviewing the P89LPC902FD,112 datasheet, P89LPC902FD,112 pinout, P89LPC902FD,112 application, or P89LPC902FD,112 equivalent, key selection criteria include its dual comparator architecture, keypad interrupt support across six Port 0 pins, 2.4–3.6 V operation with 5 V-tolerant I/O, internal RC oscillator calibration (±1 %), and compatibility with In-Application Programming (IAP-Lite) for field firmware updates.

Technical Context

The P89LPC902FD,112 implements a high-performance accelerated 2-clock 80C51 CPU executing instructions in two to four clocks, enabling 111–222 ns cycle times at 18 MHz. Its architecture embeds system-level functions including a dedicated watchdog timer with independent on-chip oscillator, brownout reset detection, and configurable port output modes (quasi-bidirectional, open-drain, push-pull).

It features five keypad interrupt inputs (KBI0, KBI2, KBI4–KBI6) mapped exclusively to Port 0 pins, two analog comparators (CMP1 and CMP2) with dedicated inputs and outputs, and a programmable internal RC oscillator selectable via Flash configuration bits - eliminating need for external crystal components in many designs.

Key Specifications

Pinout & Package

Package: Plastic small outline package; 8 leads; body width 7.5 mm (SOT96-1). Pin numbering follows standard SO-8 convention with pin 1 at top-left corner (notch or mark side).

Key Features

Applications

Equivalent & Alternatives

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

Compared with P89LPC901FD,112, the P89LPC902FD,112 adds a second comparator and three additional keypad interrupts - enabling richer analog monitoring and more responsive user interfaces. Against P89LPC903FD,112, it trades UART connectivity for dual analog sensing capability - making it optimal for standalone, sensor-dense edge nodes without host communication requirements.

Availability

P89LPC902FD,112 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart thermostat interfaces, portable medical devices, and LED lighting controllers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for P89LPC902FD,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, formerly Philips Semiconductors, is a global leader in high-performance mixed-signal ICs for automotive, industrial, and consumer applications, with deep expertise in 8-bit microcontroller architectures and embedded system integration.

The P89LPC90x family was designed specifically for ultra-compact, low-power embedded control tasks where minimal external components, analog sensing capability, and robust keypad interface are essential - targeting cost-sensitive, space-constrained applications in industrial and consumer markets.

FAQ

What is the maximum operating frequency of the P89LPC902FD,112?

The P89LPC902FD,112 supports a maximum CPU clock frequency of 18 MHz when using an external crystal or resonator. With the internal RC oscillator, the maximum calibrated frequency is 18 MHz (factory-trimmed to ±1 %), and users may fine-tune it via the TRIM register. At 18 MHz, instruction cycle times range from 111 ns to 222 ns, delivering six times the throughput of a standard 80C51 at the same clock rate.

Does the P89LPC902FD,112 support In-System Programming (ISP)?

Yes, the P89LPC902FD,112 supports Serial Flash In-Circuit Programming (ICP) using commercial EPROM programmers and In-Application Programming (IAP-Lite) for runtime firmware updates. IAP-Lite allows the P89LPC902FD,112 to reprogram its own Flash memory while executing user code - enabling field upgrades, configuration changes, and secure bootloader implementation without external programming hardware.

How many analog comparators does the P89LPC902FD,112 have, and what are their I/O assignments?

The P89LPC902FD,112 includes two independent analog comparators: CMP1 and CMP2. CMP1 uses CIN1A (P0.4) as its positive input and CMPREF (P0.5) as its negative reference; its output is available on P0.6. CMP2 uses CIN2A (P0.2) as its positive input and shares CMPREF (P0.5) as its negative reference; its output appears on P0.0. Both comparators support hysteresis and can generate interrupts.

Can the P89LPC902FD,112 operate without an external crystal?

Yes, the P89LPC902FD,112 can operate entirely without external crystal components by selecting its high-accuracy internal RC oscillator - factory-calibrated to ±1 % and fine-tunable via the TRIM register. This option supports frequencies from 20 kHz up to 18 MHz and eliminates BOM cost, board space, and layout sensitivity associated with crystal oscillators - ideal for cost-optimized and space-constrained designs.

What are the power supply requirements and I/O voltage tolerances for the P89LPC902FD,112?

The P89LPC902FD,112 operates from a 2.4 V to 3.6 V VDD supply and draws as little as 1 µA in Power-down mode (with comparators disabled). All I/O pins are 5 V tolerant - they may be safely pulled up to or driven by signals up to 5.5 V - enabling direct interfacing with legacy 5 V logic, sensors, or displays without external level-shifting circuitry.