ds1302英文.pdf

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G INFORMATION
PART # DESCRIPTION
DS1302 Serial Timekeeping Chip;
8–pin DIP
DS1302S Serial Timekeeping Chip;
8–pin SOIC (200-mil)
DS1302Z Serial Timekeeping Chip;
8–pin SOIC (150-mil)
DESCRIPTION
The DS1302 Trickle Charge Timekeeping Chip contains a real time clock/calendar and 31 bytes of static
RAM. It communicates with a microprocessor via a simple serial interface. The real time clock/calendar
provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is
automatically adjusted for months with less than 31 days, including corrections for leap year. The clock
operates in either the 24–hour or 12–hour format with an AM/PM indicator.
1 of 13 070299DS1302
Interfacing the DS1302 with a microprocessor is simplified by using synchronous serial communication.
Only three wires are required to communicate with the clock/RAM: (1) RST (Reset), (2) I/O (Data line),
and (3) SCLK (Serial clock). Data can be transferred to and from the clock/RAM 1 byte at a time or in a
burst of up to 31 bytes. The DS1302 is designed to operate on very low power and retain data and clock
information on less than 1 microwatt.
The DS1302 is the successor to the DS1202. In addition to the basic timekeeping functions of the
DS1202, the DS1302 has the additional features of dual power pins for primary and back–up power
supplies, programmable trickle c