|
|
|
부품번호 | M41T256YMH7TR 기능 |
|
|
기능 | 256 Kbit 32K x8 SERIAL RTC | ||
제조업체 | ST Microelectronics | ||
로고 | |||
www.DataSheet4U.com
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: VCC = 4.5 to 5.5V;
VPFD = 4.2 < VPFD < 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
1/27
M41T256Y
SUMMARY DESCRIPTION
The M41T256Y Serial TIMEKEEPER® SRAM is a
low power 256 Kbit static CMOS SRAM organized
as 32K words by 8 bits. A built-in 32.768kHz oscil-
lator (external crystal controlled) and 8 bytes of the
SRAM (see Table 3., page 14) are used for the
clock/calendar function and are configured in bina-
ry coded decimal (BCD) format.
Addresses and data are transferred serially via a
two line, bi-directional I2C interface. The built-in
address register is incremented automatically af-
ter each WRITE or READ data byte.
The M41T256Y has a built-in power sense circuit
which detects power failures and automatically
switches to the battery supply when a power fail-
ure occurs. The energy needed to sustain the
SRAM and clock operations can be supplied by a
lithium button-cell supply when a power failure oc-
curs. Functions available to the user include a
non-volatile, time-of-day clock/calendar, and Pow-
er-on Reset. The eight clock address locations
contain the year, month, date, day, hour, minute,
second, and tenths/hundredths of seconds in 24-
hour BCD format. Corrections for 28, 29 (leap year
- valid until year 2100), 30 and 31 day months are
made automatically. The first clock address loca-
tion (7FF8h) stores the clock software calibration
settings as well as the Write Clock Bit.
The M41T256Y is supplied in a 44-lead SOIC
SNAPHAT® package (MH - which integrates both
crystal and battery in a single SNAPHAT top) or a
44-pin “hatless” SOIC (MT). The 44-pin, 330mil
SOIC provides sockets with gold-plated contacts
at both ends for direct connection to a separate
SNAPHAT housing containing the battery and
crystal. The unique design allows the SNAPHAT
battery/crystal package to be mounted on top of
the SOIC package after the completion of the sur-
face-mount process.
Insertion of the SNAPHAT housing after reflow
prevents potential battery and crystal damage due
to the high temperatures required for device sur-
face-mounting. The SNAPHAT housing is also
keyed to prevent reverse insertion. The 44-pin
SOIC and crystal/battery packages are shipped
separately in plastic, anti-static tubes or in Tape &
Reel form. For the 44-lead SOIC, the battery/crys-
tal package (e.g., SNAPHAT) part number is
“M4Txx-BR12SH” (see Table 15., page 25).
Caution: Do not place the SNAPHAT battery/crys-
tal top in conductive foam, as this will drain the lith-
ium, button-cell battery.
Figure 3. Logic Diagram
VCC VBAT(1)
XI(1)
XO(1)
SCL
SDA
TP
M41T256Y
RST
FT
VSS
AI04754b
Note: 1. For 44-pin SNAPHAT (MT) package only.
Table 1. Signal Names
XI(1)
Oscillator Input
XO(1)
Oscillator Output
FT Frequency Test (Open drain)
RST
Reset Output (Open drain)
SCL
Serial Clock Input
SDA
Serial Data Input/Output
VCC Supply Voltage
VBAT(1)
Battery Supply Voltage
VSS Ground
TP Tamper Input
Note: 1. For 44-pin SNAPHAT (MT) package only.
4/27
4페이지 Figure 7. Serial Bus Data Transfer Sequence
DATA LINE
STABLE
DATA VALID
(SCL) CLOCK
M41T256Y
(SDA) DATA
START
CONDITION
CHANGE OF
DATA ALLOWED
Figure 8. Acknowledgement Sequence
SCL FROM
MASTER
START
1
DATA OUTPUT
BY TRANSMITTER
MSB
DATA OUTPUT
BY RECEIVER
2
STOP
CONDITION
AI04756
CLOCK PULSE FOR
ACKNOWLEDGEMENT
89
LSB
AI00601
7/27
7페이지 | |||
구 성 | 총 27 페이지수 | ||
다운로드 | [ M41T256YMH7TR.PDF 데이터시트 ] |
당사 플랫폼은 키워드, 제품 이름 또는 부품 번호를 사용하여 검색할 수 있는 |
구매 문의 | 일반 IC 문의 : 샘플 및 소량 구매 ----------------------------------------------------------------------- IGBT, TR 모듈, SCR 및 다이오드 모듈을 포함한 광범위한 전력 반도체를 판매합니다. 전력 반도체 전문업체 상호 : 아이지 인터내셔날 사이트 방문 : [ 홈페이지 ] [ 블로그 1 ] [ 블로그 2 ] |
부품번호 | 상세설명 및 기능 | 제조사 |
M41T256YMH7TR | 256 Kbit 32K x8 SERIAL RTC | ST Microelectronics |
DataSheet.kr | 2020 | 연락처 | 링크모음 | 검색 | 사이트맵 |