This document introduces the performance characteristics of a certain brand and model of notebook computer
The EM78P257 is an 8‑bit microcontroller built with low‑power, high‑speed CMOS technology. It includes a 2K × 13‑bit one‑time programmable ROM, 80 × 8‑bit SRAM registers, and a variety of built‑in peripherals such as timers, comparators, and an infrared output.
The document provides complete specifications, including operating voltage and temperature ranges, package options, pin functions, and timing parameters, as well as a functional block diagram and register descriptions.
| Operating voltage range | 2.3 V ~ 5.5 V |
|---|---|
| Operating temperature range (commercial) | 0 °C ~ 70 °C |
| On‑chip OTP ROM size | 2 K × 13 bits |
| On‑chip SRAM registers | 80 × 8 bits |
| Typical current consumption at 5 V, 4 MHz | < 1.5 mA |
The device operates from 2.3 V to 5.5 V.
The EM78P257A DIP package has 18 pins.
The OTP ROM is 2 K × 13 bits.
Yes, it has a programmable free‑running watchdog timer.