Microchip Technology MCP79410T-I/SN

Overview

MCP79410T-I/SN from Microchip Technology is a battery-backed I²C Real-Time Clock/Calendar (RTCC) IC with integrated 64-byte SRAM, 1 Kbit EEPROM, and digital trimming. It maintains time across hours/minutes/seconds/day/month/year with leap-year compensation to 2399, operates from 1.8V–5.5V, draws just 1.2 µA at 3.3V, and supports alarm-triggered MFP output in industrial temperature range (–40°C to +85°C). Used in smart meters, industrial HMIs, and backup-power-critical embedded systems.

For engineers reviewing the MCP79410T-I/SN datasheet, MCP79410T-I/SN pinout, MCP79410T-I/SN application, or MCP79410T-I/SN equivalent, key selection factors include its ±1 ppm digital trim resolution, power-fail timestamp logging, dual programmable alarms, open-drain MFP configurability, and compatibility with 6–9 pF 32.768 kHz crystals - all verified for industrial-grade reliability and I²C 400 kHz operation.

Technical Context

The MCP79410T-I/SN implements a fully autonomous RTCC using an on-chip oscillator circuit optimized for external 32.768 kHz tuning fork crystals with 6–9 pF load capacitance. Its digital trimming engine provides ±129 ppm adjustment range in ±1 ppm steps, directly compensating crystal tolerance and temperature drift without external components.

It features dual independent alarm modules with maskable comparison on seconds through month, a multifunction pin (MFP) supporting alarm assertion, selectable square-wave output (32.768 kHz, 1024 Hz, 32 Hz, 1 Hz), or general-purpose output, and automatic VCC-to-VBAT switchover at 1.3–1.7 V with timestamp capture of both power-loss and power-restoration events.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Small Outline Integrated Circuit), RoHS-compliant, surface-mount, body size 3.9 mm × 4.9 mm, lead pitch 1.27 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar real-time clock/calendar applications.

Compared with MCP79411T-I/SN, the MCP79410T-I/SN offers identical RTCC, SRAM, and EEPROM functionality but ships unprogrammed in the 64-bit protected area - simplifying custom ID provisioning. Versus DS3231M+, the MCP79410T-I/SN trades ±2 ppm TCXO stability for integrated memory, dual alarms, and digital trimming - better suited for cost-sensitive, feature-rich embedded timing.

Availability

MCP79410T-I/SN is available at Aetrix Electronics and suitable for smart metering, industrial HMI, medical portable devices, and building automation controllers requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MCP79410T-I/SN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog, FPGA, and timing solutions, serving automotive, industrial, communications, and consumer markets with vertically integrated silicon and development tools.

The MCP7941X product line delivers highly integrated, low-power RTC/Calendar ICs with embedded memory and digital calibration - designed specifically for applications demanding accurate, battery-backed timekeeping without external support components.

FAQ

What is the primary function of the MCP79410T-I/SN?

The MCP79410T-I/SN is a battery-backed I²C Real-Time Clock/Calendar IC that maintains accurate time and date (hours, minutes, seconds, day, month, year, weekday) with leap-year compensation to 2399. It integrates 64-byte SRAM, 1 Kbit EEPROM, digital trimming, dual alarms, and power-fail timestamping - all in a single 8-pin SOIC package. The MCP79410T-I/SN serves as a self-contained timing engine for embedded systems requiring reliable, low-power timekeeping across power interruptions.

Does the MCP79410T-I/SN support external crystal oscillators?

Yes, the MCP79410T-I/SN supports external 32.768 kHz tuning fork crystals connected between X1 and X2 pins. It is optimized for crystals with 6–9 pF load capacitance and includes on-chip digital trimming to compensate for frequency variance. The ST bit in RTCSEC register must be set to enable the oscillator. The MCP79410T-I/SN also supports external 32.768 kHz clock input on X1 (with X2 floating) when EXTOSC bit is set in the CONTROL register.

How does the MCP79410T-I/SN handle power loss and recovery?

The MCP79410T-I/SN automatically switches to VBAT backup supply when VCC drops below 1.3–1.7 V, preserving RTC time, SRAM contents, and register state. It logs exact timestamps of both power-fail (switchover to VBAT) and power-up (return to VCC) events in dedicated PWRDNxxx and PWRUPxxx registers. This dual-timestamp capability enables precise failure analysis and uptime tracking without host MCU involvement - a core feature of the MCP79410T-I/SN design.

What memory resources are included in the MCP79410T-I/SN?

The MCP79410T-I/SN includes three memory blocks: (1) 64-byte battery-backed SRAM (addresses 0x20–0x5F), (2) 1 Kbit (128-byte) EEPROM with software write-protection and 1M endurance, and (3) 8-byte (64-bit) protected EEPROM accessible only after a specific unlock sequence. Unlike MCP79411T-I/SN and MCP79412T-I/SN, the MCP79410T-I/SN ships with this protected area unprogrammed - allowing end users to store custom identifiers or security keys.

Can the MFP pin of the MCP79410T-I/SN be used as a general-purpose output?

Yes, the MFP (Multifunction Pin) of the MCP79410T-I/SN can be configured as a general-purpose open-drain output by clearing the SQWEN and ALMxEN bits and setting the OUT bit in the CONTROL register. It supports three modes: alarm assertion (ALM0IF/ALM1IF), selectable square-wave output (32.768 kHz, 1024 Hz, 32 Hz, or 1 Hz), or GPIO. A pull-up resistor to VCC is required in all configurations. This flexibility makes the MFP pin central to system-level event signaling in the MCP79410T-I/SN implementation.