Part UPD4991A
Description 4-BIT PARALLEL I/O CALENDAR CLOCK
Manufacturer NEC
Size 133.55 KB
NEC

UPD4991A Overview

Key Features

  • Time (hour, minute, and second) and calendar (leap year, year, month, day, and date) counters
  • Leap year can be automatically identified or set
  • 12- and 24-hour modes selectable
  • 4-bit parallel input/output in BCD data format
  • Alarm function (hour, minute, second, month, day, date)
  • One of 0.1, 1.0, 10, 30, and 60-s interval timer outputs selectable
  • One of 2048, 1024, 64, 16, 1 Hz, 1-pulse output, and H→L output selectable as alarm coincidence output
  • Upward compatible with µPD4991
  • Low power consumption: 2 µA typ. (VDD = 2.4 V)