HT1380/HT1381 -- Serial Timekeeper Chip

General Description

The HT1380/HT1381 is a serial timekeeper IC which provides seconds, minutes, hours, day, date, month and year information. The number of days in each month and leap years are automatically adjusted. The HT1380/HT1381 is designed for low power consumption and can operate in two modes: one is the 12-hour mode with an AM/PM indicator, the other is the 24-hour mode.

The HT1380/HT1381 has several registers to store the corresponding information with 8-bit data format. A 32768Hz crystal is required to provide the correct timing. In order to minimize the pin number, the HT1380/HT1381 use a serial I/O transmission method to interface with a microprocessor. Only three wires are required: (1) RESTB, (2) SCLK and (3) I/O. Data can be delivered 1 byte at a time or in a burst of up to 8 bytes. 

Features

  • Operating voltage: 2.0V~5.5V
  • Maximum input serial clock: 500kHz at VDD=2V, 2MHz at VDD=5V
  • Operating current: less than 400nA at 2V, less than 1.2uA at 5V
  • TTL compatible
    - VIH: 2.0V~VDD+0.3V at VDD=5V
    - VIL: -0.3V~+0.8V at VDD=5V
  • Two data transmission modes: single-byte or burst mode
  • Serial I/O transmission
  • All registers store BCD format
  • HT1380: 8-pin DIP package
    HT1381: 8-pin SOP package

技术相关信息

其它相关信息