MCP79410T-I/MNY

Real Time Clock Overview

The MCP79410T-I/MNY is a battery-backed I2C Real-Time Clock/Calendar (RTCC) IC manufactured by Microchip Technology. It operates within an industrial temperature range of -40°C to +85°C and supports supply voltages from 1.8V to 5.5V, with backup voltage support from 1.3V to 5.5V. The device tracks time using internal counters for hours, minutes, seconds, day of week, date, month, and year, supporting both 12-hour and 24-hour formats. Key electrical parameters include a typical timekeeping current of 1.2µA at 3.3V on VCC and 925nA at 3.0V on VBAT. It features a 2-wire serial interface compatible with I2C clock rates up to 400 kHz.

Real Time Clock Feature Summary

• Integrated 64-byte battery-backed SRAM and 1 Kbit EEPROM with software write-protect capabilities.
• Dual programmable alarms with flexible comparison options and a versatile multifunction output pin.
• On-chip digital trimming/calibration with ±1 ppm resolution and ±129 ppm range for oscillator accuracy.
• Power-fail timestamp module that logs time during switchover to and from battery mode.

Real Time Clock Applications

• Real-time clock and calendar tracking in embedded systems requiring low power consumption.
• Data logging applications utilizing the power-fail timestamp feature for event recording.
• Devices requiring non-volatile storage for user data or configuration via SRAM and EEPROM.

Real Time Clock Procurement Notes

Verify the specific package variant, as the 'MNY' suffix denotes the 8-WFDFN (2x3) package with exposed pad. Confirm the operating temperature grade corresponds to the 'I' suffix (-40°C to +85°C). Ensure the master controller supports the required I2C addressing scheme, noting distinct control bytes for EEPROM versus RTCC/SRAM registers. Check for any relevant errata documents regarding the specific revision level.

Real Time Clock Selection Notes

Select this component when a compact surface-mount solution is required for timekeeping with integrated non-volatile memory. The MCP79410 differs from the MCP79411 and MCP79412 by lacking pre-programmed EUI-48 or EUI-64 MAC addresses in the protected EEPROM area; it contains unprogrammed protected EEPROM instead. Consider the 8-TDFN package constraints and ensure appropriate load capacitors are selected for the external 32.768 kHz crystal to meet frequency tolerance requirements.

Real Time Clock Part Context

This part belongs to the MCP7941X family of battery-backed I2C RTCCs, which also includes the MCP79410T-I/MS (MSOP package), MCP79410T-I/SN (SOIC package), and MCP79410T-I/TSSOP. The family shares identical functional specifications but varies in physical packaging. The T-I/MNY designation specifically identifies the tape-and-reel version of the industrial-grade device in the 8-lead Thin Dual Flat No-lead (TDFN) package.

Real Time Clock Replacement Considerations

Direct pin-compatible replacements within the same package include other variants of the MCP7941X family such as MCP79410T-I/MS or MCP79410T-I/SN, provided the PCB footprint accommodates the specific package dimensions. Note that substituting with MCP79411 or MCP79412 models will result in different contents in the protected EEPROM area (EUI-48/EUI-64 addresses vs. unprogrammed).