DS1302Z datasheet by Dallas Semiconductor

DS1302Z Frequently Asked Questions (FAQs)

• What is the recommended power-on reset circuit for the DS1302Z?
  A simple RC circuit with a 1kΩ resistor and a 10μF capacitor is recommended to ensure a clean power-on reset. This circuit helps to prevent the clock from starting up in an unknown state.
• How do I handle the case where the battery is removed and reinserted?
  When the battery is removed and reinserted, the DS1302Z will retain its clock data for a short period of time (typically up to 10 minutes). To ensure accurate timekeeping, it's recommended to reset the clock to a known state (e.g., 00:00:00) after battery reinsertion.
• What is the maximum clock frequency that can be used with the DS1302Z?
  The DS1302Z can operate with clock frequencies up to 32.768 kHz. However, it's recommended to use a 32.768 kHz crystal oscillator to ensure accurate timekeeping and minimize power consumption.
• How do I ensure that the DS1302Z is properly initialized after power-up?
  After power-up, the DS1302Z should be initialized by writing the correct values to the clock registers (seconds, minutes, hours, etc.). It's also recommended to clear the oscillator stop flag (OSF) and the clock halt flag (CH) to ensure proper clock operation.
• What is the purpose of the EOSC (Enable Oscillator) bit in the DS1302Z?
  The EOSC bit is used to enable or disable the internal oscillator circuit. When set to 1, the oscillator is enabled, and when set to 0, the oscillator is disabled. This bit should be set to 1 during normal operation to ensure accurate timekeeping.