MCP79410-I/SN

The MCP7941X Real-Time Clock/Calendar (RTCC)
tracks time using internal counters for hours, minutes,
seconds, days, months, years, and day of week. Alarms
can be configured on all counters up to and including
months. For usage and configuration, the MCP7941X
supports I2C communications up to 400 kHz.
The open-drain, multi-functional output can be
configured to assert on an alarm match, to output a
selectable frequency square wave or as a general
purpose output.
The MCP7941X is designed to operate using a
32.768 kHz tuning fork crystal with external crystal load
capacitors. On-chip digital trimming can be used to
adjust for frequency variance caused by crystal
tolerance and temperature.
SRAM and timekeeping circuitry are powered from the
backup supply when main power is lost, allowing the
device to maintain accurate time and the SRAM
contents. The times when the device switches over to
the back-up supply and when primary power returns are
both logged by the power-fail timestamp.
The MCP7941X features 1 Kbit of internal nonvolatile
EEPROM with software write-protectable regions. There
is an additional 64 bits of protected nonvolatile memory
which is only writable after an unlock sequence, making
it ideal for storing a unique ID or other critical
information. The MCP79411 and MCP79412 are
preprogrammed with EUI-48 and EUI-64 addresses,
respectively. Custom programming is also available.