NXP Semiconductors P87C54X2FBD,157

Overview

P87C54X2FBD,157 from NXP Semiconductors (formerly Philips) is a 16 KB OTP-based 8-bit microcontroller in the enhanced 80C51 family, operating at up to 33 MHz (12-clock mode) or 30 MHz (6-clock mode) across 2.7–5.5 V supply, featuring 256 B RAM, three 16-bit timers (T0/T1/T2), full-duplex UART with framing error detection, and four 8-bit I/O ports - deployed in industrial control panels requiring deterministic real-time response and field-upgradable firmware.

For engineers reviewing the P87C54X2FBD,157 datasheet, P87C54X2FBD,157 pinout, P87C54X2FBD,157 application, or P87C54X2FBD,157 equivalent, key selection criteria include OTP security bit configuration (3-bit), LQFP-44 package compatibility with extended temperature range (–40 °C to +85 °C), dual clock-mode flexibility (6/12-clock software-selectable), power-down wake-up via INT0/INT1, and programmable clock-out on P1.0.

Technical Context

This device implements a static CMOS 80C51 CPU core with Boolean processor support, fully compatible with MCS-51 instruction set and memory map. It supports both 6-clock (2× throughput per oscillator cycle) and 12-clock operation modes, controlled by CKCON.X2 SFR bit and OTP OX2 bit - enabling runtime clock scaling without hardware change.

The architecture integrates three independent 16-bit counter/timers: T0 and T1 retain standard 80C51 functionality, while T2 adds capture/compare, reload, and programmable clock-out capability. The enhanced UART supports automatic address recognition and framing error detection, and all I/O ports feature internal pull-ups with configurable alternate functions mapped to P1.0/T2 and P1.1/T2EX.

Key Specifications

Pinout & Package

Package: Plastic low-profile quad flat package (LQFP-44), body size 10 × 10 × 1.4 mm, lead pitch 0.8 mm, JEDEC MS-026 compliant (SOT389-1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT89C55WD-24PU and P89C54X2FA,118, the P87C54X2FBD,157 uniquely combines OTP security, LQFP-44 compactness, and T2-based clock-out - making it optimal for cost-sensitive, production-hardened control modules where firmware integrity and board area are critical constraints.

Availability

P87C54X2FBD,157 is available at Aetrix Electronics and suitable for industrial motor control, smart energy metering, building automation panels, and legacy PLC I/O modules requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for P87C54X2FBD,157 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-reliability mixed-signal ICs for automotive, industrial, and IoT applications, with deep heritage in 8-bit microcontroller innovation since the 1980s.

The P87C54X2FBD,157 belongs to the P87C5xX2 OTP-enhanced 80C51 family, designed specifically for cost-optimized, long-lifecycle industrial control applications demanding robustness, security, and minimal external components.

FAQ

What is the maximum operating frequency of the P87C54X2FBD,157 and how does clock mode affect it?

The P87C54X2FBD,157 supports up to 33 MHz in 12-clock mode and 30 MHz in 6-clock mode at 5 V. In 6-clock mode, each instruction executes in half the time versus 12-clock mode - effectively doubling throughput without increasing oscillator frequency. The CKCON.X2 bit controls this dynamically, and the OTP OX2 bit can permanently fix 6-clock operation during programming.

Does the P87C54X2FBD,157 support external memory expansion, and what pins are involved?

Yes, the P87C54X2FBD,157 supports external program and data memory via its multiplexed P0 (AD0–AD7) and P2 (A8–A15) buses. P3.6/WR and P3.7/RD provide strobes for external RAM access, while PSEN enables external program memory reads. EA/VPP must be held low to activate external code fetches below 0000H–3FFFH address space.

How is the programmable clock-out function implemented on the P87C54X2FBD,157?

The P87C54X2FBD,157 generates a 50% duty-cycle clock on P1.0 using Timer 2 in clock-out mode. This requires clearing C/T2 (T2CON.1), setting T2OE (T2MOD.1), and enabling TR2 (T2CON.2). The output frequency depends on oscillator speed and RCAP2H/L reload value - ranging from 61 Hz to 4 MHz at 16 MHz OSC in 12-clock mode.

What power-saving modes does the P87C54X2FBD,157 offer, and how are they exited?

The P87C54X2FBD,157 offers Idle mode (CPU halted, peripherals active) and Power-down mode (oscillator stopped, RAM retained). Idle exits via any enabled interrupt or reset. Power-down exits via hardware reset or level-sensitive external interrupt on INT0/INT1 - controlled by WUPD bit (AUXR1.3) - with oscillator stabilization taking <10 ms before resuming execution.

Is the P87C54X2FBD,157 pin-compatible with other members of the P87C5xX2 family?

Yes, the P87C54X2FBD,157 shares identical LQFP-44 pinout and signal mapping with P87C51X2FBD, P87C52X2FBD, and P87C58X2FBD - differing only in OTP ROM size (4 KB/8 KB/16 KB/32 KB) and RAM (128 B/256 B). This enables scalable design reuse across product tiers without PCB redesign.