M41T94 Datasheet, PDF (1/31 Pages) STMicroelectronics – 512 Bit 64 bit x8 SERIAL RTC SPI SRAM

M41T94
512 Bit (64 bit x8) SERIAL RTC (SPI) SRAM
FEATURES SUMMARY
s 2.7 TO 5.5V OPERATING VOLTAGE
s SERIAL PERIPHERAL INTERFACE (SPI)
s 2.5 TO 5.5V OSCILLATOR OPERATING
VOLTAGE
s AUTOMATIC SWITCH-OVER and DESELECT
CIRCUITRY
s CHOICE OF POWER-FAIL DESELECT
VOLTAGES (V_CC = 2.7 to 5.5V):
– THS = V_SS; 2.55V ≤ V_PFD ≤ 2.70V
– THS = V_CC; 4.20V ≤ V_PFD ≤ 4.50V
s COUNTERS FOR TENTHS/HUNDREDTHS
OF SECONDS, SECONDS, MINUTES,
HOURS, DAY, DATE, MONTH, YEAR, and
CENTURY
s 44 BYTES OF GENERAL PURPOSE RAM
s PROGRAMMABLE ALARM and INTERRUPT
FUNCTION (VALID EVEN DURING BATTERY
BACK-UP MODE)
s WATCHDOG TIMER
s MICROPROCESSOR POWER-ON RESET
s BATTERY LOW FLAG
s LOW OPERATING CURRENT OF 2.0mA
s ULTRA-LOW BATTERY SUPPLY CURRENT
OF 500nA (MAX)
s PACKAGING INCLUDES A 28-LEAD SOIC and
SNAPHAT^® TOP (to be ordered separately) or
16-LEAD SOIC
s 28-LEAD SOIC PACKAGE PROVIDES
DIRECT CONNECTION FOR A SNAPHAT
TOP WHICH CONTAINS THE BATTERY and
CRYSTAL
Figure 1. 16-pin SOIC Package
16
1
SO16 (MQ)
Figure 2. 28-pin SOIC Package
SNAPHAT (SH)
Battery & Crystal
28
1
SOH28 (MH)
June 2003
Rev. 2.0
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