M41ST87WSS6F STMicroelectronics, M41ST87WSS6F Datasheet - Page 33

• Manufacturer Part Number: M41ST87WSS6F
• Description: IC SUPERVISOR RTC/NVRAM 20-SSOP
• Manufacturer: STMicroelectronics
• Type: Clock/Calendar/Supervisorr

Specifications of M41ST87WSS6F

• Memory Size: 160B
• Time Format: HH:MM:SS:hh (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SSOP
• Function: Clock, Timestamp, Timekeeper, Watchdog, Alarm, Calendar, Timer, Timer Interrupt
• Rtc Memory Size: 1280 bit
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.7 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Rtc Bus Interface: Serial
• Supply Current: 500 nA
• Clock Format: Ss
• Clock Ic Type: RTC
• Interface Type: I2C
• Memory Configuration: 128 X 8
• Supply Voltage Range: 2.7V To 3.6V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-10616-2

M41ST87Y, M41ST87W
Figure 22. Crystal accuracy across temperature
Figure 23. Calibration waveform
3.3
NORMAL
POSITIVE
CALIBRATION
NEGATIVE
CALIBRATION
Frequency (ppm)
–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
M41ST87Y/W is in the battery back-up to serve as a system wake-up call.
Bits RPT5–RPT1 put the alarm in the repeat mode of operation.
the possible configurations. Codes not listed in the table default to the once per second
mode to quickly alert the user of an incorrect alarm setting.
When the clock information matches the alarm clock settings based on the match criteria
defined by RPT5–RPT1, the AF (alarm flag) is set. If AFE (alarm flag enable) is also set, the
20
0
–40
–30
–20
–10
0
Doc ID 9497 Rev 9
10
Temperature °C
F
K
= –0.036 ppm/°C
= K x (T – T
20
T
30
O
= 25°C ± 5°C
O
)
2
40
2
± 0.006 ppm/°C
50
60
Table 8 on page 34
2
70
80
Clock operation
AI07888
AI00594B
shows
33/54