MCS@51 8-BIT CONTROL-ORIENTED MICROCONTROLLERS are microcontrollers optimized for control applications. They have high performance, internal timers/event counters, a 2-level interrupt priority structure, 32 I/O lines, and 64KB external program memory space, among other features.
The Intel MCS‑51 family comprises a range of 8‑bit control‑oriented microcontrollers such as the 8031AH, 8051AH, 8051AHP, 8751H and related variants. The devices offer up to 64 KB of external program and data memory, 32 I/O lines, multiple timers, and a full‑duplex serial interface, all built on high‑performance HMOS processes.
The datasheet details package options (40‑pin DIP, CERDIP, 44‑pin PLCC), pin functions, oscillator configurations, absolute maximum ratings, operating conditions, and DC characteristics. It also describes the EXPRESS version with extended temperature ranges and optional burn‑in testing.
| Operating Temperature (Commercial) | 0 °C to +70 °C |
|---|---|
| Operating Temperature (Express) | -40 °C to +85 °C |
| Supply Voltage (Voc) | 5.5 V |
| Oscillator Frequency | up to 12 MHz |
| External Program Memory Space | 64 KB |
| External Data Memory Space | 64 KB |
| I/O Lines | 32 (four 8‑bit ports) |
The EXPRESS version operates from –40 °C to +85 °C.
Each device provides 32 I/O lines organized as four 8‑bit ports.
It protects the EPROM against unauthorized readout and prevents code fetching from external program memory.
The devices support oscillator frequencies up to 12 MHz.