AN1759 datasheet(2/24 Pages) FREESCALE

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Application Note

AN1759

The non-volatile RAM (random-access memory) also gives the user

additional applications such as:

• Power down information storage for consumer electronics like

TVs, VCRs, and hand-held portables

• Identification number storage for remote addressing or security

• Storage of telecommunication information like phone number

recall and speed dialing

This application note describes the interface between the

MC68HC705J1A (J1A) and the DS1307. Circuitry and example code are

given to demonstrate the interface between the two parts.

Features

The DS1307 provides these features:

• Real-time clock counts seconds, minutes, hours, day of the week,

date, month, and year.

• Leap year compensation valid up to 2100

• 56 bytes of non-volatile RAM for data storage

• 2-wire serial interface

• Programmable square wave output with frequencies of 1 Hz,

4.096 kHz, 8.192 kHz, and 32.768 kHz

• Automatic power switching to battery when main power fails

• In battery backup mode, less than 500 nA consumed at 25 °C

• 8-pin DIP or SOIC package

• Optional industrial temperature range of –40 °C to +85 °C

Description

The DS1307 is a low-power binary coded decimal (BCD) clock calendar

that provides seconds, minutes, hours, day, date, month, and year. In

addition, it has 56 bytes of non-volatile RAM. End-of-the-month

adjustments are automatic for months with less than 31 days. The

device also corrects for leap years. The clock can operate in either

12-hour or 24-hour mode. In 12-hour mode, an a.m./p.m indicator is

used.

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

AN1759 датащи(PDF) 2 Page - Freescale Semiconductor, Inc