MCP79401T-I/MS

Real Time Clock Overview

The MCP79401T-I/MS is a battery-backed I2C Real-Time Clock/Calendar (RTCC) in an 8-lead MSOP package. It tracks time using internal counters for hours, minutes, seconds, day of week, date, month, and year, with leap year compensation through 2399. The device operates on a supply voltage of 1.8V to 5.5V and draws 1.2 µA at 3.3V during timekeeping. It includes 64 bytes of battery-backed SRAM and 8 bytes of protected EEPROM preprogrammed with an EUI-48 MAC address. Features include dual programmable alarms, digital trimming, and automatic switchover to backup power.

Real Time Clock Feature Summary

• I2C compatible serial interface supporting clock rates up to 400 kHz
• 64-byte battery-backed SRAM and 8-byte protected EEPROM with EUI-48 address
• Dual programmable alarms and versatile multifunction output pin
• On-chip digital trimming with ±1 ppm resolution for oscillator calibration

Real Time Clock Applications

• Embedded systems requiring precise timekeeping and calendar functions
• Devices needing non-volatile storage for unique identifiers or critical data
• Battery-powered applications utilizing automatic power switchover

Real Time Clock Procurement Notes

Verify the specific suffix 'MS' corresponds to the 8-lead MSOP package type. Confirm the 'I' designation indicates the industrial temperature range of -40°C to +85°C. Ensure the part number includes the 'T' for tape and reel packaging if required for assembly processes.

Real Time Clock Selection Notes

Select this component when an I2C RTCC with integrated MAC address storage is required. The MCP79401 is distinct from the MCP79400 (unprogrammed EEPROM) and MCP79402 (EUI-64 address). Verify that the application supports the 1.8V to 5.5V operating voltage range and requires the specific 8-lead MSOP footprint.

Real Time Clock Part Context

This part belongs to the MCP7940X family of battery-backed RTCCs. The MCP79401 variant is specifically distinguished by its factory-programmed EUI-48™ MAC address in the protected EEPROM area. It shares functional similarities with the MCP79400 and MCP79402 but differs in EEPROM content and package options.

Real Time Clock Replacement Considerations

The MCP79400T-I/MS serves as a functional substitute if the preprogrammed EUI-48 address is not required. The MCP79402T-I/MS is an alternative if an EUI-64 address is needed instead. Package variations such as TSSOP or SOIC are available under different suffixes.