NXP Semiconductors P89LPC922FN,112

Overview

P89LPC922FN,112 from NXP Semiconductors (formerly Philips) is an 8-bit microcontroller based on a two-clock 80C51 core, featuring 8 kB Flash memory, 256-byte RAM, and operation from 2.4 V to 3.6 V with 5 V-tolerant I/O. It integrates dual 16-bit timers, real-time clock, two analog comparators, enhanced UART with fractional baud rate generator, and 400 kHz I²C bus - deployed in low-cost industrial control and sensor interface applications.

For engineers reviewing the P89LPC922FN,112 datasheet, P89LPC922FN,112 pinout, P89LPC922FN,112 application, or P89LPC922FN,112 equivalent, key selection considerations include its DIP20 package compatibility, 18 MHz max operating frequency, on-chip RC oscillator calibrated to ±1%, and support for In-Application Programming of Flash memory.

Technical Context

The P89LPC922FN,112 executes instructions in two to four CPU clocks - six times faster than standard 80C51 at the same frequency - enabling 111 ns minimum instruction cycle time at 18 MHz. Its dual-clock architecture decouples peripheral clocking (PCLK = CCLK/2) from CPU execution, allowing independent timing control for UART, I²C, timers, and RTC.

It supports four oscillator sources: factory-trimmed 7.373 MHz RC oscillator (±1%), 400 kHz watchdog oscillator, external crystal (20 kHz–18 MHz), or external clock input. Clock source selection is configured via Flash configuration bits, and CLKOUT on XTAL2 provides CCLK/2 output when crystal is unused and RTC does not depend on it.

Key Specifications

Pinout & Package

Package: Plastic dual in-line package (DIP20), 20 leads, 300 mil width, SOT146-1 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with P89LPC922FDH, the P89LPC922FN,112 offers identical functionality in a through-hole DIP20 package for prototyping and legacy repair, while P89LPC921FDH reduces Flash capacity but maintains full peripheral and timing compatibility - enabling scalable design reuse across product tiers.

Availability

P89LPC922FN,112 is available at Aetrix Electronics and suitable for industrial control, sensor interface, and legacy equipment modernization requiring stable component supply, long-term obsolescence mitigation, and through-hole manufacturing compatibility.

Supply support for P89LPC922FN,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 acquired Philips Semiconductors in 2006 and continues to support legacy LPC microcontroller families with documentation, tools, and long-term supply assurance.

The P89LPC92x series was designed for cost-sensitive, low-power embedded applications where integration of Flash, analog peripherals, and flexible clocking reduces BOM count - targeting industrial automation, building controls, and appliance subsystems.

FAQ

What is the maximum operating frequency of the P89LPC922FN,112?

The P89LPC922FN,112 supports a maximum system clock frequency of 18 MHz when using the high-speed oscillator option with an external crystal or resonator. At this frequency, its two-clock 80C51 core achieves a minimum instruction cycle time of 111 ns. The on-chip RC oscillator is factory trimmed to 7.373 MHz ±1% and can be fine-tuned via the TRIM register for stability across voltage and temperature.

Does the P89LPC922FN,112 support in-circuit programming?

Yes, the P89LPC922FN,112 supports both Serial Flash Programming for in-circuit production coding and In-Application Programming (IAP) for runtime firmware updates without removing the device from the target system. Flash security bits prevent unauthorized readout of sensitive application code, and programming is performed via the UART or I²C interface using standard ISP protocols defined in the user manual.

What are the power supply requirements for the P89LPC922FN,112?

The P89LPC922FN,112 operates from a single 2.4 V to 3.6 V supply (VDD), with VSS as the 0 V reference. All I/O pins are 5 V tolerant and may be pulled up to or driven by 5.5 V logic - enabling direct interfacing with legacy 5 V peripherals without level shifters. Brownout detection provides graceful shutdown below 2.4 V, and Power-down mode draws just 1 µA typical current when comparators are disabled.

How many I/O pins does the P89LPC922FN,112 provide?

The P89LPC922FN,112 provides 15 dedicated I/O pins minimum, expanding to 18 when using on-chip oscillator and reset options. Port 0 (P0.0–P0.7), Port 1 (P1.0–P1.7), and Port 3 (P3.0–P3.1) collectively deliver configurable digital I/O, with Port 0 supporting hardware keyboard interrupt pattern matching and all pins featuring Schmitt-triggered inputs for noise immunity.

Is the P89LPC922FN,112 pin-compatible with other members of the P89LPC92x family?

Yes, the P89LPC922FN,112 shares identical pinout and electrical characteristics with P89LPC920FDH, P89LPC921FDH, and P89LPC922FDH in the same package type - meaning DIP20 variants (e.g., P89LPC922FN,112 and P89LPC9221FN) are fully pin-compatible, and TSSOP20 variants share pinout across Flash sizes. However, P89LPC9221 variants offer higher drive current (20 mA) on selected pins, which is not present in the P89LPC922FN,112.