NXP Semiconductors P80C31SBPN,112

Overview

P80C31SBPN,112 from Philips Semiconductors is a ROMless 8-bit 80C51 microcontroller with 128 × 8 RAM, four 8-bit I/O ports, three 16-bit counter/timers, and a full-duplex UART. It operates from 2.7 V to 5.5 V at up to 16 MHz and supports idle and power-down modes for low-power embedded control in industrial monitoring systems.

For engineers reviewing the P80C31SBPN,112 datasheet, P80C31SBPN,112 pinout, P80C31SBPN,112 application, or P80C31SBPN,112 equivalent, key selection factors include its static CMOS design enabling zero-frequency operation, external memory interface capability via multiplexed Port 0/2, and hardware interrupt structure with six sources and four priority levels.

Technical Context

The P80C31SBPN,112 implements a static 8051 CPU core with Boolean processor, dual data pointers, and full instruction set compatibility with Intel 8051. Its architecture supports external program and data memory access using 64 KB address spaces each, with Port 0 serving as AD0–AD7 and Port 2 as A8–A15 during external fetches.

It features a programmable clock-out on P1.0 (61 Hz–4 MHz at 16 MHz oscillator), Timer 2 with capture/auto-reload/baud-rate generation modes, and power management including software-controllable idle mode (CPU halted, peripherals active) and power-down mode (oscillator stopped, RAM retained down to 2.0 V).

Key Specifications

Pinout & Package

Package: Plastic Dual In-line Package (PDIP), 40-pin, SOT129-1, operating 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 and DS89C430-QCL+, the P80C31SBPN,112 uniquely supports external program memory execution and ultra-low-power static operation-making it optimal for legacy-compatible, field-upgradable, and battery-sensitive designs where ROM capacity exceeds 4 KB or clock flexibility is critical.

Availability

P80C31SBPN,112 is available at Aetrix Electronics and suitable for industrial PLC I/O modules, legacy equipment controllers, smart energy meter interfaces, and embedded security keypads requiring stable component supply across extended product lifecycles.

Supply support for P80C31SBPN,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 Dutch semiconductor company founded in 1953, specializing in analog, logic, and microcontroller solutions for industrial and automotive markets.

The 80C31/80C32 family was designed as ROMless members of the 80C51 platform to enable flexible, cost-effective embedded control with external memory expandability and low-voltage operation for legacy system upgrades.

FAQ

What is the maximum operating frequency of the P80C31SBPN,112?

The P80C31SBPN,112 is rated for up to 16 MHz operation across its full 2.7 V–5.5 V supply range. Its static CMOS design permits operation at any frequency down to 0 Hz, enabling deterministic clock gating and ultra-low-power idle states without data corruption. This specification is confirmed in the Philips 80C31/80C32 Product Specification (2000 Aug 07), Section "SELECTION TABLE" and "FEATURES".

Does the P80C31SBPN,112 include on-chip program memory?

No, the P80C31SBPN,112 is a ROMless device with zero kilobytes of on-chip program memory. It executes code exclusively from external program memory accessed via PSEN, ALE, and the multiplexed Port 0/Port 2 bus. This is explicitly stated in the Philips datasheet "SELECTION TABLE" and "DESCRIPTION" sections, distinguishing it from variants like the 80C51RA+ which integrate flash ROM.

How does the P80C31SBPN,112 handle power-down mode exit?

The P80C31SBPN,112 exits power-down mode via hardware reset or external interrupt on INT0/INT1. Upon reset, all Special Function Registers (SFRs) are reinitialized but on-chip RAM retains its contents; with an enabled level-sensitive interrupt, both RAM and SFRs preserve state. The datasheet confirms wakeup is always enabled for the 80C31 variant, requiring VCC stabilization before releasing the interrupt signal.

Can the P80C31SBPN,112 generate precise clock signals for external circuits?

Yes, the P80C31SBPN,112 can generate precise 50% duty-cycle clocks on P1.0 using Timer 2 in clock-out mode. At 16 MHz operation, frequencies range from 61 Hz to 4 MHz, calculated as OSC/(4 × (65536 − RCAP2H:RCAP2L)). This capability is documented in the "Programmable Clock-Out" section of the Philips datasheet and requires configuration of T2CON and T2MOD registers.

What packaging and temperature grade does P80C31SBPN,112 use?

The P80C31SBPN,112 uses a 40-pin Plastic Dual In-line Package (PDIP) per drawing SOT129-1, rated for commercial temperature range 0 °C to +70 °C. This is specified in the "80C51/87C51 AND 80C31 ORDERING INFORMATION" table, where the suffix "B" denotes 0–70 °C and "PN" indicates PDIP packaging.