STMicroelectronics M41T81SMY6F Linear IC User Manuals

Table of Contents

• 1 Description

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  • Figure 1. Logic diagram

    6
  • Table 1. Signal names

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  • Figure 2. 8-pin SOIC (M) connections

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  • Figure 3. 18-pin, 300 mil SOIC (MY) connections

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  • Figure 4. Block diagram

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• 2 Operation

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  • 2-wire bus characteristics

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  • Bus not busy

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  • Start data transfer

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  • Stop data transfer

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  • Data valid

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  • Acknowledge

    10
    • Figure 5. Serial bus data transfer sequence

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    • Figure 6. Acknowledgement sequence

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  • READ mode

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    • Figure 7. Slave address location

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    • Figure 8. READ mode sequence

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    • Figure 9. Alternative READ mode sequence

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  • WRITE mode

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  • Data retention mode

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    • Figure 10. WRITE mode sequence

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• 3 Clock operation

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  • Power-down time-stamp

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  • Clock registers

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    • Table 2. Clock register map

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  • Calibrating the clock

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    • Figure 11. Crystal accuracy across temperature

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    • Figure 12. Clock calibration

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  • Setting alarm clock registers

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    • Figure 13. Alarm interrupt reset waveform

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    • Figure 14. Backup mode alarm waveform

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    • Table 3. Alarm repeat modes

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  • Watchdog timer

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  • Square wave output

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    • Table 4. Square wave output frequency

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  • Century bit

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  • Battery low warning

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  • Oscillator fail detection

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  • Oscillator fail interrupt enable

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  • Output driver pin

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  • Preferred initial power-on default

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    • Table 5. Preferred default values

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• 4 Maximum ratings

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  • Table 6. Absolute maximum ratings

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• 5 DC and AC parameters

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  • Table 7. Operating and AC measurement conditions

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  • Figure 15. AC measurement I/O waveform

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  • Table 8. Capacitance

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  • Table 9. DC characteristics

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  • Table 10. Crystal electrical characteristics

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  • Figure 16. Power down/up mode AC waveforms

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  • Table 11. Power down/up AC characteristics

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  • Table 12. Power down/up trip points DC characteristics

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  • Figure 17. Bus timing requirements sequence

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  • Table 13. AC characteristics

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• 6 Package mechanical data

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  • Figure 18. SO8 - 8-lead plastic small package outline

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  • Table 14. SO8 - 8-lead plastic small outline (150 mils body width), package mechanical data

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  • Figure 19. SOX18 - 18-lead plastic small outline, 300 mils, embedded crystal, outline

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  • Table 15. SOX18 - 18-lead plastic small outline, 300 mils, embedded crystal, package mechanical data

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• 7 Part numbering

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  • Table 16. Ordering information

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• 8 Revision history

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