M41T56_11 STMICROELECTRONICS [STMicroelectronics], M41T56_11 Datasheet - Page 15

• Manufacturer Part Number: M41T56_11
• Description: Serial real-time clock (RTC) with 56 bytes NVRAM
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M41T56
3.2
Note:
3.3
Figure 11. Crystal accuracy across temperature
Figure 12. Clock calibration
Output driver pin
When the FT bit is not set, the FT/OUT pin becomes an output driver that reflects the
contents of D7 of the control register. In other words, when D6 of location 7 is a '0' and D7 of
location 7 is a '0' and then the FT/OUT pin will be driven low.
The FT/OUT pin is open drain which requires an external pull-up resistor.
Initial power-on defaults
Upon initial application of power to the device, the FT bit will be set to a '0' and the OUT bit
will be set to a '1.' All other register bits will initially power-on in a random state.
NORMAL
POSITIVE
CALIBRATION
NEGATIVE
CALIBRATION
Frequency (ppm)
–100
–120
–140
–160
–20
–40
–60
–80
20
0
–40
–30
–20
–10
Doc ID 6104 Rev 9
0
10
Temperature °C
ΔF = K x (T –T
T
F
K = –0.036 ppm/°C
O
= 25°C ± 5°C
20
30
O
)
2
40
2
± 0.006 ppm/°C
50
60
2
Clock operation
70
80
AI00594B
AI00999b
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