R2025中文资料高精度I2C总线实时时钟模块数据手册Nisshinbo规格书

描述 Description

The R2025 is a real-time clock module, built in CMOS real-time clock IC and crystal oscillator, connected to the CPU by two signal lines, SCL and SDA, and configured to perform serial transmission of time and calendar data to the CPU. The oscillation frequency is adjusted to high precision (0±5ppm: 13sec. per month at 25°C) The periodic interrupt circuit is configured to generate interrupt signals with six selectable interrupts ranging from 0.5 seconds to 1 month. The 2 alarm interrupt circuits generate interrupt signals at preset times. As the oscillation circuit is driven under constant voltage, fluctuation of the oscillator frequency due to supply voltage is small, and the time keeping current is small (TYP. 0.48 µA at 3V). The oscillation halt sensing circuit can be used to judge the validity of internal data in such events as power-on; The supply voltage monitoring circuit is configured to record a drop in supply voltage below two selectable supply voltage monitoring threshold settings. The 32-kHz clock output function (CMOS output) is intended to output sub-clock pulses for the external microcomputer. The oscillation adjustment circuit is intended to adjust time by correcting deviations in the oscillation frequency of the crystal oscillator.

特性 Features

• Built in crystal unit：32.768 kHz, The oscillation frequency is adjusted to high precision (0±5ppm: at 25°C)；
• Time keeping voltage：1.15 V to 5.5 V；
• Supply Current：Typ. 0.48 µA (VDD=3V)；
• Connected to the CPU：I2C-Bus interface (Maximum serial clock frequency: 400 KHz at VDD≥1.7V)；
• Functions：Time counters (counting hours, minutes, and seconds) and calendar counters (counting years, months, days, and weeks) (in BCD format)；
• Interrupt circuit configured to generate interrupt signals (with interrupts ranging from 0.5 seconds to 1 month) to the CPU and provided with an interrupt flag and an interrupt halt；
• 2 alarm interrupt circuits (Alarm_W for week, hour, and minute alarm settings and Alarm_D for hour and minute alarm settings)；
• With Power-on flag to prove that the power supply starts from 0V；
• With Oscillation halt sensing Flag to judge the validity of internal data；
• Supply voltage monitoring circuit with two supply voltage monitoring threshold settings；
• Automatic identification of leap years up to the year 2099；
• Selectable 12-hour and 24-hour mode settings；
• Built-in Circuits：Oscillation adjustment circuit for correcting temperature frequency deviation or offset deviation；
• Clock Output：32.768 kHz (CMOS push-pull output with control pin)；
• Packages：SON22, SOP14；

应用 Application

• Home appliances such as refrigerators, rice cookers, and electric pots
• Digital appliances such as laptops, digital TVs, DSCs, camcorders, mobile phones, and private LAN system
• Office appliances such as copiers, printers, facsimiles, scanners, and projectors