M48T08Y-10MH1E STMicroelectronics, M48T08Y-10MH1E Datasheet - Page 15
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M48T08Y-10MH1E
Manufacturer Part Number
M48T08Y-10MH1E
Description
IC TIMEKPR NVRAM 64KBIT 5V 28SOI
Manufacturer
STMicroelectronics
Series
Timekeeper®r
Type
Clock/Calendar/NVSRAMr
Datasheet
1.M48T08Y-10MH1F.pdf
(31 pages)
Specifications of M48T08Y-10MH1E
Memory Size
64K (8K 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
28-SOIC, 28-SOH (8.48mm Width)
Function
Clock/Calendar/NV Timekeeping RAM/Battery Backup
Rtc Memory Size
8192 Byte
Supply Voltage (max)
5.5 V
Supply Voltage (min)
4.5 V
Maximum Operating Temperature
+ 70 C
Minimum Operating Temperature
0 C
Mounting Style
SMD/SMT
Rtc Bus Interface
Parallel
Clock Format
HH
Clock Ic Type
Timekeeper
Memory Configuration
8K X 8
Supply Voltage Range
4.75V To 5.5V
Digital Ic Case Style
SOH
No. Of Pins
28
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Other names
497-2830-5
M48T08Y-10MH1
M48T08Y-10MH1
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
M48T08Y-10MH1E
Manufacturer:
SMSC
Quantity:
5 213
M48T08, M48T08Y, M48T18
3.3
Note:
3.4
Table 5.
Keys:
Stopping and starting the oscillator
The oscillator may be stopped at any time. If the device is going to spend a significant
amount of time on the shelf, the oscillator can be turned off to minimize current drain on the
battery. The STOP bit (ST) is the MSB of the seconds register. Setting it to a '1' stops the
oscillator. The M48T08/18/08Y (in the PCDIP28 package) is shipped from
STMicroelectronics with the STOP bit set to a '1.' When reset to a '0,' the M48T08/18/08Y
oscillator starts within one second.
To guarantee oscillator startup after initial power-up, first write the STOP bit (ST) to '1,' then
reset to '0.'
Calibrating the clock
The M48T08/18/08Y is driven by a quartz-controlled oscillator with a nominal frequency of
32,768 Hz. A typical M48T08/18/08Y is accurate within 1 minute per month at 25 °C without
calibration. The devices are tested not to exceed ± 35 ppm (parts per million) oscillator
frequency error at 25 °C, which equates to about ±1.53 minutes per month. With the
calibration bits properly set, the accuracy of each M48T08/18/08Y improves to better than
+1/–2 ppm at 25 °C.
The oscillation rate of any crystal changes with temperature.
frequency error that can be expected at various temperatures. Most clock chips compensate
for crystal frequency and temperature shift error with cumbersome “trim” capacitors. The
Address
1FFFh
1FFEh
1FFDh
1FFCh
1FFBh
1FFAh
1FF9h
1FF8h
S = SIGN bit
FT = FREQUENCY TEST bit (set to '0' for normal clock operation)
R = READ bit
W = WRITE bit
ST = STOP bit
0 = Must be set to '0'
Register map
D7
ST
W
0
0
0
0
0
D6
FT
R
10 years
0
0
0
10 seconds
10 minutes
D5
S
0
0
10 hours
10 date
Doc ID 2411 Rev 10
10 M
D4
0
Data
D3
0
Calibration
D2
Seconds
Minutes
Month
Hours
Date
Year
Day
D1
Figure 8 on page 17
D0
Seconds
Minutes
Control
Month
Hours
Date
Year
Day
Function/range
BCD format
Clock operations
shows the
00-99
01-12
01-31
01-07
00-23
00-59
00-59
15/31