M41T256Y Datasheet, PDF (1/27 Pages) STMicroelectronics – 256 Kbit 32K x8 SERIAL RTC

M41T256Y
256 Kbit (32K x8) Serial RTC
FEATURES SUMMARY
■ 5V OPERATING VOLTAGE
■ SERIAL INTERFACE SUPPORTS
EXTENDED I²C BUS ADDRESSING
(400kHz)
■ AUTOMATIC SWITCH-OVER AND
DESELECT CIRCUITRY
■ POWER-FAIL DESELECT VOLTAGES:
– M41T256Y: V_CC = 4.5 to 5.5V;
V_PFD = 4.2 < V_PFD < 4.5V
■ COUNTERS FOR TENTHS/HUNDREDTHS
OF SECONDS, SECONDS, MINUTES,
HOURS, DAY, DATE, MONTH, and YEAR
■ PROGRAMMABLE SOFTWARE CLOCK
CALIBRATION
■ 32,752 BYTES OF GENERAL PURPOSE
RAM
■ MICROPROCESSOR POWER-ON RESET
■ HOLDS MICROPROCESSOR IN RESET
UNTIL SUPPLY VOLTAGE REACHES
STABLE OPERATING LEVEL
■ AUTOMATIC ADDRESS-INCREMENTING
■ TAMPER INDICATION CIRCUIT WITH TIME-
STAMP
■ SLEEP MODE FUNCTION
■ PACKAGING INCLUDES A 44-LEAD SOIC
AND SNAPHAT^® TOP (to be ordered
separately)
■ SOIC PACKAGE PROVIDES DIRECT
CONNECTION FOR A SNAPHAT^® TOP
WHICH CONTAINS THE BATTERY AND
CRYSTAL
Figure 1. 44-pin, Hatless SOIC Package
44
1
SO44 (MT)
Figure 2. 44-pin SOIC Package
SNAPHAT (SH)
Crystal/Battery
44
1
SOH44 (MH)
June 2004
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