M48T37Y-70MH1E STMicroelectronics, M48T37Y-70MH1E Datasheet - Page 13

• Manufacturer Part Number: M48T37Y-70MH1E
• Description: IC TIMEKPR NVRAM 256KBIT5V 44SOH
• Manufacturer: STMicroelectronics
• Series: Timekeeper®r
• Type: Clock/Calendar/NVSRAMr

Specifications of M48T37Y-70MH1E

• Memory Size: 256K (32K x 8)
• Time Format: HH:MM:SS (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 44-SOH
• Bus Type: Parallel
• User Ram: 32KB
• Operating Supply Voltage (typ): 5V
• Package Type: SOH
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 44
• Mounting: Surface Mount
• Memory Configuration: 32K X 8
• Nvram Features: RTC
• Interface Type: Parallel
• Access Time: 70ns
• Supply Voltage Range: 4.5V To 5.5V
• Memory Case Style: SOIC
• No. Of Pins: 44
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-2854-5; M48T37Y-70MH1

Table 5. Register Map
Keys: S = Sign Bit
Address
7FFDh
7FFCh
7FFFh
7FFEh
7FFBh
7FFAh
7FF9h
7FF8h
7FF7h
7FF6h
7FF5h
7FF4h
7FF3h
7FF2h
7FF1h
7FF0h
FT = Frequency Test Bit
R = READ Bit
W = WRITE Bit
ST = Stop Bit
0 = Must be set to '0'
BL = Battery Low Flag (Read only)
BMB0-BMB4 = Watchdog Multiplier Bits
RPT4
RPT3
RPT2
RPT1
WDS
WDF
AFE
D7
ST
W
0
0
0
0
0
BMB4
D6
FT
AF
R
0
0
0
0
0
0
1000 Year
10 Years
Alarm 10 Seconds
Alarm 10 Minutes
10 Seconds
10 Minutes
BMB3
AIarm 10 Hours
ABE
AIarm 10 Date
D5
S
Z
0
0
10 Hours
10 Date
BMB2
10 M
D4
BL
0
0
Data
BMB1
D3
0
0
Z
Calibration
Date: Day of Month
BMB0
Alarm Seconds
Alarm Minutes
D2
Alarm Hours
Alarm Date
Z
0
100 Year
Seconds
Minutes
AFE = Alarm Flag Enable Flag
RB0-RB1 = Watchdog Resolution Bits
WDS = Watchdog Steering Bit
ABE = Alarm in Battery Back-Up Mode Enable Bit
RPT1-RPT4 = Alarm Repeat Mode Bits
WDF = Watchdog Flag (Read only)
AF = Alarm Flag (Read only)
Z = '0' and are Read only
Month
Hours
Year
Day of Week
RB1
D1
Z
0
RB0
D0
0
Z
M48T37Y, M48T37V
Alarm Hour
Alarm Date
Alarm Sec
Watchdog
Alarm Min
Interrupts
Century
Control
Month
Hours
Flags
Year
Date
Function/Range
Day
Sec
Min
BCD Format
00-99
01-12
01-31
00-23
00-59
00-59
01-31
00-23
00-59
00-59
00-99
01-7
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