ST5372 Low-Power RTC IC
Specifications
Alarm Sets2
Periodic IN2Hz to 1 Month (2Hz / 1Hz / 1/60Hz / 1/3600Hz / monthly selectable)
Standby400nA (typ. @3.6V)
CLK/INT OOpen Drain
Clock Adj.Yes
I/OI²C Two-wire Serial
Clock VDD1.8 ~ 5.5V
Work VDD1.8 ~ 5.5V
Accuracy-
PackageSOP-8 / TSSOP-8
ReferenceRS5C372A
Product details
Overview
The ST5372 is a low-power real-time clock (RTC) circuit that communicates with a CPU in real time via a two-wire I²C interface, primarily used in systems that require a time base. The chip can generate various periodic interrupt pulses (with a maximum period of up to one month) and features two alarm systems. An integrated low-power regulated supply allows the oscillator to operate at very low power even under harsh conditions (400nA typ. at 3.6V). Latched crystal oscillation-stop detection verifies the validity of internal clock data, and a digital time adjustment circuit ensures high-accuracy timekeeping with support for both 32.768KHz and 32KHz crystal modes.
Features
- Ultra-low power consumption: 400nA typ. at 3.6V
- Real-time clock with 12-hour or 24-hour mode
- Automatic leap-year recognition (2000 to 2099)
- BCD-coded time counting (hours, minutes, seconds) and perpetual calendar (leap/common year, month, day, weekday)
- 30-second digital time correction
- Selectable 32.768KHz or 32KHz frequency output
- Two programmable alarm outputs
- Two programmable square-wave outputs; periodic interrupts from 1 second to 1 month
- I²C two-wire interface with up to 100KHz data clock
- Crystal oscillation stop detection with latching ensures clock data validity
- High-precision digital time adjustment circuit for accurate timekeeping
- Ultra-low voltage operation: timekeeping and communication down to 1.8V
- SOP-8 / TSSOP-8 package; fully compatible with Ricoh RS5C372A
