NXP Semiconductors P89LPC938FA,129

Overview

P89LPC938FA,129 from NXP Semiconductors (formerly Philips) is an 8-bit accelerated 2-clock 80C51 microcontroller with 8 kB Flash, 10-bit ADC, dual analog comparators, and integrated CCU for PWM/capture/compare functions. It operates from 2.4 V to 3.6 V with 5 V-tolerant I/O, supports up to 18 MHz internal RC or crystal clocking, and targets low-cost embedded control in space-constrained industrial sensors and power management modules.

For engineers reviewing the P89LPC938FA,129 datasheet, P89LPC938FA,129 pinout, P89LPC938FA,129 application, or P89LPC938FA,129 equivalent, key selection criteria include its 23–26 configurable I/O count in PLCC28 package, on-chip 512-byte Data EEPROM for parameter storage, fractional baud rate UART, and hardware RTC capability derived from the 23-bit system timer.

Technical Context

The P89LPC938FA,129 implements a two-cycle-per-instruction 80C51 core delivering 111–222 ns instruction cycle times at 18 MHz-six times faster than standard 80C51 at same frequency. Its architecture integrates dedicated peripherals including a Capture/Compare Unit (CCU) supporting four independent PWM outputs (OCA–OCD), input capture (ICA/ICB), and output compare modes.

It features a programmable on-chip oscillator with selectable frequency range (20 kHz–18 MHz), separate watchdog oscillator for fail-detect, and dual analog comparators (CMP1/CMP2) with selectable reference and inputs. The 10-bit ADC supports eight channels (AD00–AD07) with burst scan and edge-triggered conversion.

Key Specifications

Pinout & Package

Package: PLCC28 (plastic leaded chip carrier, 28 leads, SOT261-2). Pin count: 28-pin layout with 23–26 usable I/O depending on oscillator/reset configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with P89LPC938FA,129, the P89LPC935FA,129 reduces non-volatile storage capability while maintaining identical I/O and timing peripherals, whereas the C8051F330-GM trades integrated EEPROM and CCU for higher-speed ADC and USB-but demands external components and software overhead to replicate core P89LPC938FA,129 functionality.

Availability

P89LPC938FA,129 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart power switches, low-power keypad interfaces, and embedded metering front-ends requiring stable component supply across extended production lifecycles.

Supply support for P89LPC938FA,129 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 P89LPC938FA,129 belongs to NXP's LPC900 family of enhanced 80C51 microcontrollers, designed specifically for cost-sensitive, space-constrained embedded control where integration of Flash, EEPROM, analog peripherals, and intelligent I/O reduces BOM count and PCB area.

FAQ

What is the maximum operating frequency supported by the P89LPC938FA,129?

The P89LPC938FA,129 supports a maximum operating frequency of 18 MHz when using either the internal RC oscillator (fine-tunable) or an external crystal/resonator. At this frequency, its accelerated 2-clock 80C51 core achieves instruction cycle times of 111–222 ns-six times faster than a standard 80C51 running at the same clock speed. This enables higher computational throughput while maintaining low power consumption and reduced EMI.

Does the P89LPC938FA,129 include on-chip non-volatile memory beyond program Flash?

Yes, the P89LPC938FA,129 includes 512-byte on-chip Data EEPROM, separate from its 8 kB Flash code memory. This EEPROM is rated for 100,000 write/erase cycles and is used for serialization, calibration data storage, and field-updatable configuration parameters. Unlike Flash, it supports true byte-level erasure and writing without sector-level constraints, making it ideal for infrequently updated runtime variables in the P89LPC938FA,129.

How many analog input channels does the 10-bit ADC in the P89LPC938FA,129 support?

The P89LPC938FA,129 integrates an 8-channel 10-bit successive-approximation ADC (ADC0), with inputs AD00 through AD07 mapped to Port 0 and Port 2 pins. Channel selection is software-configurable via the AD0INS register, and the ADC supports burst scan mode, external trigger (via T0/T1), and edge-triggered conversions-enabling synchronized sampling in sensor fusion or power monitoring applications using the P89LPC938FA,129.

Can the P89LPC938FA,129 operate without an external crystal or resonator?

Yes, the P89LPC938FA,129 features a high-accuracy internal RC oscillator that is user-selectable and fine-tunable via the TRIM register. It supports frequencies from 20 kHz up to the maximum 18 MHz, eliminating the need for external timing components in cost-sensitive or space-constrained designs. The RC oscillator option is configured using Flash configuration bits, and the P89LPC938FA,129 maintains sufficient accuracy for UART communication, RTC, and general-purpose timing tasks.

What I/O protection features are implemented on the P89LPC938FA,129?

The P89LPC938FA,129 provides 5 V-tolerant I/O pins (up to 5.5 V), Schmitt-triggered inputs on all ports for noise immunity, programmable slew-rate control (~10 ns minimum ramp time) to reduce EMI, and configurable output types (quasi-bidirectional, open-drain, push-pull, input-only) per pin. These features allow robust interfacing with mixed-voltage systems, noisy industrial environments, and LED loads-enhancing reliability without external protection circuitry in the P89LPC938FA,129.