BL5372

The BL5372 is a low-power Real-Time Clock (RTC) integrated circuit from Shanghai Belling Co., Ltd. It communicates with a CPU via a two-wire I2C interface, making it suitable for systems requiring timekeeping functions.

Key features include ultra-low power consumption (typically 400nA at 3.6V), support for both 12-hour and 24-hour time formats, and automatic recognition of leap years within the 2000-2099 range. The device provides clock counts and a perpetual calendar in BCD format, including hours, minutes, seconds, year, month, day, and day of the week. It also offers a 30-second digital time correction function and selectable crystal oscillator frequencies of 32KHz or 32.768KHz.

The BL5372 is designed to generate various periodic interrupt pulses, with periods ranging from one month down to one second. It also features two sets of alarm systems (ALARM-A and ALARM-B) and two programmable square wave outputs for CPU interrupts. The chip includes an internal low-power voltage regulator, enabling operation in harsh environments. It is available in SOP8 or TSSOP8 packages.

This RTC IC is fully compatible with the Ricoh RS5C372A, offering design flexibility. Its high-precision time adjustment circuit ensures accurate timekeeping, with an adjustment range of ±189ppm. The device supports ultra-low voltage operation, with timing voltages down to 1.8V.