NXP Semiconductors P87LPC761BN,112

Overview

P87LPC761BN,112 from NXP Semiconductors (formerly Philips) is a 16-pin, low-power, OTP-based 80C51-compatible microcontroller optimized for cost-sensitive embedded control applications. It integrates 2 kbyte on-chip EPROM, 128 byte RAM, two analog comparators, full-duplex UART, I²C interface, watchdog timer with independent oscillator, and programmable port configurations - enabling compact sensor interfaces, LED controllers, and keypad-based appliances operating from 2.7 V to 6.0 V.

For engineers reviewing the P87LPC761BN,112 datasheet, P87LPC761BN,112 pinout, P87LPC761BN,112 application, or P87LPC761BN,112 equivalent, key selection considerations include its 20 MHz/10 MHz dual-voltage clock operation, 1 µA Power Down current, quasi-bidirectional/open-drain/push-pull I/O flexibility, on-chip RC oscillator option, and 32-byte customer code space for device serialization.

Technical Context

The P87LPC761BN,112 implements an accelerated 80C51 core executing instructions in 300–600 ns at 20 MHz (VDD = 4.5–6.0 V), with selectable standard 80C51 timing via CLKR bit. Its CPU clock derives from user-configurable sources: high/medium/low-frequency crystal, external clock, or on-chip RC oscillator - all selected by EPROM configuration bits.

It features two 16-bit timers (one supporting port-output toggle on overflow), four interrupt priority levels, six keypad interrupt inputs (P0.x), two external interrupts (INT0, INT1), and dual analog comparators with internal reference and interrupt capability - all managed through dedicated SFRs including CMP1#, CMP2#, and IEN1#.

Key Specifications

Pinout & Package

Package: 16-pin plastic dual in-line package (DIP16), 300 mil body width, SOT38-1 footprint. Compatible with through-hole assembly and socket-based prototyping.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9306,118 and AT89C2051-24PU, the P87LPC761BN,112 uniquely combines OTP program storage, dual analog comparators, I²C interface, and ultra-low-power operation in a 16-pin DIP - making it irreplaceable in cost-constrained, sensor-rich embedded systems where peripheral integration reduces BOM count and layout complexity.

Availability

P87LPC761BN,112 is available at Aetrix Electronics and suitable for smart appliance control, industrial sensor interface, LED lighting control, and keypad-based security panels requiring stable component supply across extended production lifecycles.

Supply support for P87LPC761BN,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 company formed from the spin-off of Philips Semiconductors in 2006, specializing in secure connectivity solutions for automotive, industrial, and IoT markets.

The P87LPC761BN,112 belongs to NXP's legacy LPC700 family of low-pin-count 80C51 microcontrollers, designed specifically for cost-sensitive, space-constrained embedded control applications demanding high integration without external support components.

FAQ

What is the maximum operating frequency of the P87LPC761BN,112 and under what voltage conditions?

The P87LPC761BN,112 operates up to 20 MHz when supplied at 4.5 V to 6.0 V, and up to 10 MHz at 2.7 V to 6.0 V. This dual-speed specification allows designers to optimize performance versus power consumption across varying supply conditions. The P87LPC761BN,112 achieves this using an accelerated 80C51 core with 6-clock machine cycles, delivering twice the instruction throughput of standard 80C51 parts at the same frequency.

Does the P87LPC761BN,112 support in-system programming or require external EPROM programmers?

The P87LPC761BN,112 uses One-Time Programmable (OTP) EPROM and requires parallel programming via a dedicated EPROM programmer before soldering - it does not support in-system or in-circuit reprogramming. Serial EPROM programming is supported during production, but once programmed, the code memory cannot be erased or rewritten. The P87LPC761BN,112 includes two EPROM security bits to prevent unauthorized readout of sensitive firmware.

How many I/O pins are available on the P87LPC761BN,112 and what configuration options do they support?

The P87LPC761BN,112 provides a minimum of 11 dedicated I/O pins, expandable to 14 when using on-chip oscillator and reset options to free up X1, X2, and RST pins. Each I/O pin supports programmable output types - quasi-bidirectional, open-drain, push-pull, or input-only - controlled via SFRs P0M1#, P0M2#, P1M1#, P1M2#, and P2M1#. This flexibility enables direct LED drive (20 mA), I²C bus compliance, and noise-immune digital input.

What analog functions are integrated into the P87LPC761BN,112 and how are they implemented?

The P87LPC761BN,112 integrates two independent analog comparators (CMP1 and CMP2) with selectable hysteresis, internal reference voltage (CMPREF), and interrupt capability. Comparator inputs (CIN1A/CIN1B, CIN2A/CIN2B) are mapped to specific port pins, allowing direct connection to external sensors or voltage dividers. The P87LPC761BN,112 does not include an ADC; instead, it uses comparator outputs for threshold detection, window monitoring, or zero-crossing sensing - reducing component count in simple analog decision applications.

What power-saving modes does the P87LPC761BN,112 offer and how is wake-up handled?

The P87LPC761BN,112 supports Idle mode (CPU halted, peripherals active) and Power Down mode (1 µA typical current). In Power Down mode, execution resumes upon any low-level interrupt on a configured I/O pin - including external interrupts (INT0/INT1), keypad interrupts (KBI on P0.x), or comparator interrupts. The P87LPC761BN,112 also includes Brownout Detection and Power-On Reset to ensure reliable startup and graceful shutdown during supply fluctuations.