Nxp Semiconductors PCF2123 사용자 매뉴얼

차례

• 1. Introduction

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• 2. Features

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• 3. Comparison

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  • 3.1 Event counter mode

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• 4. Power-on reset (POR)

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• 5. Voltage-low detector

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• 6. Oscillator

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  • 6.1 Oscillation allowance

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  • 6.2 Using an external oscillator

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• 7. Crystal and crystal selection

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  • 7.1 Modes which don’t work

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  • 7.2 Effect of temperature

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• 8. Capacitors and capacitor selection

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• 9. Accuracy

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• 10. Oscillator tuning

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  • 10.1 PCF2123 Offset register

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• 11. Century and leap year, Daylight Saving Time

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  • 11.1 Century tracking

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  • 11.2 Year and leap year tracking

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  • 11.3 Daylight Saving Time (DST)

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• 12. Initialization and setting of alarm and timer

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  • 12.1 Initialization of the RTC and setting the time

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  • 12.2 Alarm

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  • 12.3 Setting the timer

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• 13. Backup power supply

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  • 13.1 Lithium Primary cells

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  • 13.2 NiCd and NiMH secondary batteries

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  • 13.3 Capacitors

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    • 13.3.1 Charging the backup capacitor

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    • 13.3.2 Estimation of backup time with capacitor

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  • 13.4 Diode selection

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• 14. PCB layout guidelines

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• 15. Partial circuit switch down

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• 16. Hints to keep power consumption low

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• 17. First period inaccuracy when using the timer

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• 18. Timing requirements for I2C read and write

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• 19. Troubleshooting

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  • 19.1 Oscillator startup time

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  • 19.2 Checking for oscillation

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  • 19.3 No communication via I2C-bus

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  • 19.4 Wrong time and date, wrong clock speed

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• 20. References

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• 21. Legal information

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  • 21.1 Definitions

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  • 21.2 Disclaimers

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  • 21.3 Trademarks

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• 22. Contents

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