M48T254V Datasheet, PDF (1/24 Pages) STMicroelectronics – CLOCK FUNCTION IS TRANSPARENT TO RAM OPERATION.

M48T254V
3.3V, 16 Mbit (2 Mb x 8 bit) TIMEKEEPER^®
SRAM WITH PHANTOM CLOCK
FEATURES SUMMARY
s 3.3V ± 10%
s INTEGRATED ULTRA LOW POWER SRAM,
REAL TIME CLOCK, POWER-FAIL CONTROL
CIRCUIT, BATTERY AND CRYSTAL
s REAL TIME CLOCK KEEPS TRACK OF
TENTHS/HUNDREDTHS OF SECONDS,
SECONDS, MINUTES, HOURS, DAYS, DATE,
MONTHS, and YEARS.
s CLOCK FUNCTION IS TRANSPARENT TO
RAM OPERATION.
s PRECISION POWER MONITORING and
POWER SWITCHING CIRCUITRY
s AUTOMATIC WRITE-PROTECTION WHEN
V_CC IS OUT-OF-TOLERANCE
s POWER-FAIL DESELECT VOLTAGE:
– V_CC = 3.3V ± 10%; 2.8V ≤ V_PFD ≤ 2.97V
s BATTERY LOW (BL)
s 10 YEARS of DATA RETENTION and CLOCK
OPERATION IN THE ABSENCE OF POWER
s SNAPHAT HOUSING (BATTERY/CRYSTAL)
IS REPLACEABLE
s 100ns ACCESS (READ = WRITE)
Figure 1. 168-ball PBGA Module
168-ball PBGA
Module (ZA)
Figure 2. SNAPHAT Crystal/Battery
SNAPHAT (SH)
Crystal/Battery
May 2003
Rev. 2.0
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