The DS1388Z-5+ should be placed away from high-frequency noise sources and power planes. Use a dedicated power supply and decoupling capacitors to minimize noise. Follow a star-grounding scheme and keep the crystal oscillator circuitry separate from the digital circuitry.
Use a high-quality crystal with a low equivalent series resistance (ESR) and ensure the oscillator circuit is properly biased. Apply a power-on reset (POR) signal to the DS1388Z-5+ to ensure a reliable startup. In cold temperatures, consider using a crystal with a higher drive level or adding a startup capacitor to aid in oscillator startup.
Use the SYNC pin to synchronize the DS1388Z-5+ with an external clock source. Ensure the external clock frequency is within the specified range (1 Hz to 64 kHz) and that the SYNC pin is driven with a logic-level signal. You can also use the SET pin to set the time manually.
Use a battery with a low self-discharge rate and ensure the BBRAM is properly powered down during shutdown. Use a power-down detector circuit to detect power-down and automatically switch to battery power. During power-up, use a power-up detector circuit to detect power-up and automatically switch to main power.
Implement redundant timekeeping mechanisms, such as a secondary clock source or a redundant RTC. Use error detection and correction mechanisms, such as checksums or CRCs, to ensure data integrity. Consider using a radiation-hardened or high-reliability version of the DS1388Z-5+.
DS1388Z-5+ datasheet
by Maxim Integrated Products
