m41st85w STMicroelectronics, m41st85w Datasheet - Page 22

• Manufacturer Part Number: m41st85w
• Description: 3.0/3.3v I 2c Combination Serial Rtc, Nvram Supervisor And Microprocessor Supervisor
• Manufacturer: STMicroelectronics

Figure 13. Crystal accuracy across temperature
Figure 14. Calibration waveform
3.4
22/41
Frequency (ppm)
NORMAL
POSITIVE
CALIBRATION
NEGATIVE
CALIBRATION
–100
–120
–140
–160
–20
–40
–60
–80
Setting alarm clock registers
Address locations 0Ah-0Eh contain the alarm settings. The alarm can be configured to go
off at a prescribed time on a specific month, date, hour, minute, or second, or repeat every
year, month, day, hour, minute, or second. It can also be programmed to go off while the
M41ST85W is in the battery back-up to serve as a system wake-up call.
20
0
–40
–30
–20
–10
0
10
Temperature C
F
K
F = K x (T – T
= –0.036 ppm/ C
20
T
30
O
= 25 C ± 5 C
O
)
2
40
2
± 0.006 ppm/ C
50
60
2
70
80
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AI00594B