The MCP79400-I/SN is a low-power Real-time Clock (RTC) uses digital timing compensation for an accurate clock/calendar, a programmable output control for versatility, a power sense circuit that automatically switches to the backup supply and non-volatile memory for data storage. Using a 32.768kHz crystal, it tracks time using several internal registers. For communication, the MCP7940X uses the I²C™ bus. The clock/calendar automatically adjusts for months with fewer than 31 days, including corrections for leap years. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator and settable alarm(s) to the second, minute, hour, day of the week, date or month. Along with the battery-backed SRAM memory, a 64-bit protected EEPROM space is available for unique ID or MAC address to be programmed at the factory or by the end user.
● On-chip digital trimming/calibration - 1ppm Resolution
● Dual alarm with single output
● Programmable open-drain output control - CLKOUT with 4 selectable frequencies and alarm output
● 64-byte SRAM, battery backed
● Automatic VCC switchover to VBAT backup supply
● Power-fail time-stamp for battery switchover
● Low-power CMOS technology
● 1 Million erase/write cycles for unique ID
● 64-bit Unique ID - User or factory programmable and protected EEPROM
