W78C52D is an 8-bit microcontroller with a wider frequency and supply voltage range than most 8-bit microcontrollers on the market. It is compatible with the industry standard 80C52 microcontroller series.
This manual describes the W78C52D microcontroller, highlighting its wider frequency and supply voltage range, compatibility with the 80C52 series, and its on‑chip resources such as RAM, ROM, timers, and serial port. It includes detailed pin configurations, functional block diagrams, and electrical characteristics.
Additional sections cover power‑management features (idle and power‑down modes), the watchdog timer operation, absolute maximum ratings, and example application circuits. Package dimensions for DIP, PLCC, and QFP variants are also provided.
| Supply voltage range | 4.5 V to 5.5 V |
|---|---|
| Maximum operating frequency | DC‑40 MHz |
| On‑chip RAM | 256 bytes |
| On‑chip ROM | 8 KB mask ROM |
| Operating temperature range | 0 °C to 70 °C |
| Idle current (5 V, 20 MHz) | 6 mA |
| Power‑down current (5 V, no load) | 50 µA |
| Number of 8‑bit I/O ports | Four |
| Extra bit‑addressable I/O port | 4‑bit (Port 4) |
| Additional external interrupts | INT2, INT3 |
The device operates from 4.5 V to 5.5 V.
It has four 8‑bit bidirectional ports plus an extra 4‑bit bit‑addressable port (Port 4).
The microcontroller supports an idle mode and a power‑down mode, both selectable by software.
The part can run up to 40 MHz.