NXP Semiconductors P80C32UBPN,112

Overview

P80C32UBPN,112 from Philips Semiconductors is a ROMless 8-bit 80C51-compatible microcontroller with 256 × 8 RAM, 33 MHz maximum operating frequency, and low-voltage operation (2.7 V–5.5 V). It integrates three 16-bit counter/timers, a full-duplex UART with framing error detection, four 8-bit I/O ports, and supports idle and power-down power control modes - deployed in industrial control panels requiring deterministic real-time response under wide-temperature ambient conditions.

For engineers reviewing the P80C32UBPN,112 datasheet, P80C32UBPN,112 pinout, P80C32UBPN,112 application, or P80C32UBPN,112 equivalent, key selection criteria include its static CMOS design enabling zero-frequency stop-clock operation, dual data pointer support for efficient external memory access, and hardware-level interrupt prioritization across six sources with four priority levels - all critical for legacy embedded firmware porting and long-lifecycle industrial maintenance.

Technical Context

The P80C32UBPN,112 implements a static 80C51 core fabricated in Philips high-density CMOS technology, supporting full compatibility with MCS-51 instruction set and memory-mapped peripheral architecture. Its internal timing relies on an on-chip oscillator driven by XTAL1/XTAL2, with ALE output at 1/6 oscillator frequency for external address latching during MOVX accesses.

Power management includes two software-selectable low-power states: idle mode freezes CPU execution while preserving RAM, timers, UART, and interrupt logic; power-down mode halts the oscillator and disables all peripherals except RAM retention down to 2.0 V. Wake-up from power-down is enabled via INT0 or INT1 when configured as level-sensitive inputs and WUPD bit (AUXR1.3) is set.

Key Specifications

Pinout & Package

Package: Plastic Dual In-line Package (PDIP), 40-pin, SOT129-1, commercial temperature range (0 °C to +70 °C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT89C51-24PI, P80C32UBPN,112 offers superior real-time determinism via Timer 2 capture and dual DPTR, while DS80C320-QCL+ delivers faster instruction execution but demands firmware adaptation - making P80C32UBPN,112 optimal for stable, long-lifecycle industrial designs requiring proven reliability over raw speed.

Availability

P80C32UBPN,112 is available at Aetrix Electronics and suitable for industrial PLC I/O modules, legacy automotive body controllers, and medical infusion pump controllers requiring stable component supply across extended product lifecycles.

Supply support for P80C32UBPN,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

Philips Semiconductors (now NXP Semiconductors) is a pioneer in CMOS-based microcontrollers, delivering high-reliability silicon for industrial and automotive markets since the 1980s.

The 80C31/80C32 family was designed specifically for ROMless embedded control applications demanding low power, wide voltage tolerance, and full 8051 software compatibility - targeting cost-sensitive, long-lifecycle systems where external EPROM or Flash is preferred.

FAQ

What is the maximum operating frequency of the P80C32UBPN,112 and under what voltage conditions is it guaranteed?

The P80C32UBPN,112 is rated for a maximum operating frequency of 33 MHz at VCC = 5.0 V. This specification is guaranteed across the full commercial temperature range (0 °C to +70 °C) and within the 2.7 V–5.5 V supply range - though 33 MHz operation requires VCC ≥ 4.5 V per Philips datasheet timing characterization. At 2.7 V, the maximum supported frequency is 16 MHz.

Does the P80C32UBPN,112 include on-chip ROM or Flash memory?

No, the P80C32UBPN,112 is a ROMless device - it contains no internal program memory. It executes code exclusively from external program memory (e.g., EPROM or Flash) accessed via P0 and P2 address/data buses and controlled by PSEN and EA/VPP signals. This architecture allows field-upgradable firmware and flexible memory sizing.

How does the power-down mode of the P80C32UBPN,112 preserve data and what wake-up sources are supported?

In power-down mode, the P80C32UBPN,112 stops the oscillator and disables all peripherals except on-chip RAM and Special Function Registers, which retain their values down to 2.0 V. Wake-up is supported via hardware reset or level-sensitive external interrupts on INT0 or INT1 - provided WUPD bit (AUXR1.3) is set and VCC is restored to ≥2.7 V before wake-up assertion.

What are the key differences between Timer 2 in the P80C32UBPN,112 and the standard 8051 Timer 0/1?

Unlike Timer 0 and Timer 1, Timer 2 in the P80C32UBPN,112 supports three distinct modes: capture, auto-reload (up/down), and baud-rate generation. It features dedicated RCAP2H/RCAP2L registers, T2EX input for external reload/capture control, and independent RCLK/TCLK bits enabling separate transmit/receive baud rates - capabilities absent in baseline 8051 timers.

Is the P80C32UBPN,112 pin-compatible with other members of the 80C51 family such as the 80C51 or 80C31?

Yes, the P80C32UBPN,112 uses the standard 40-pin PDIP footprint and identical pinout as the 80C31 and 80C51 families - including identical signal assignments for P0–P3, RST, XTAL1/XTAL2, ALE, PSEN, and EA/VPP. This allows direct substitution in existing 8051-based designs, provided firmware accounts for the larger 256-byte RAM and presence of Timer 2.