m41t80 STMicroelectronics, m41t80 Datasheet - Page 17

• Manufacturer Part Number: m41t80
• Description: Serial Access Real Time Clock With Alarm
• Manufacturer: STMicroelectronics

M41T80
3.5
Note:
3.6
Output driver pin
When the AFE Bit and SQWE Bit are not set, the IRQ/OUT/SQW pin becomes an output
driver that reflects the contents of D7 of the Control Register. In other words, when D7 (OUT
Bit) of address location 08h is a '0,' then the IRQ/OUT/SQW pin will be driven low.
The IRQ/OUT/SQW pin is an open drain which requires an external pull-up resistor.
Preferred power-on default
When powering the device up from ground (0V), the following register bits are set to a '0'
state: ST; AFE; and SQWE. The following bits are set to a '1' state: OUT and 32kE (see
Table 6: Preferred power-on default values on page
Table 6.
1. If V
Power-up
CC
falls to a voltage, 0V < V
(1)
Condition
Preferred power-on default values
CC
< 2.0V, these bits should be rewritten by the user.
ST
0
Out
1
17).
AFE
0
SQWE
0
Clock operation
32kE
1
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