SPI RTC with integrated trickle charge
The DS1391U-18 is an SPI real-time clock from Analog Devices that integrates a battery-charge circuit with trickle charging, so a backup supercap or lithium coin cell stays topped off without an external charge-management IC.
Active lifecycle and RoHS limitation
It is listed as RoHS non-compliant, so designs requiring RoHS exemption or lead-free assembly must verify the exemption category or consider a pin-compatible alternative with RoHS certification.