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STMicroelectronics M41T81M6F — Discrete Semiconductors

M41T81M6F RTC, Clock/Calendar, I2C, 8-SOIC, Active

MPNM41T81M6F
End of Life

STMicroelectronics M41T81M6F Clock/Calendar RTC, I²C interface, 2-5.5V, alarm, watchdog, 8-SOIC, Tape & Reel.

$3.06Ref. price · indicative, final on quote
Packaging8-SOIC (0.154", 3.90mm Width)
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

M41T81M6F specifications
ParameterValue
TypeClock/Calendar
MountingSurface Mount
Supply voltage2V ~ 5.5V
Voltage - supply, battery2.5V ~ 3.5V
Current - timekeeping100µA @ 2V ~ 5.5V
InterfaceI²C, 2-Wire Serial
Operating temperature-40°C ~ 85°C
PackageTape & Reel (TR); Cut Tape (CT)
FeaturesAlarm, Leap Year, Square Wave Output, Watchdog Timer
Date formatYY-MM-DD-dd
Time formatHH:MM:SS:hh (24 hr)
Case8-SOIC (0.154\", 3.90mm Width)

Product details

RTC with I²C bus and on-chip timers

The M41T81M6F is an I²C-compatible real-time clock from STMicroelectronics, providing timekeeping in HH:MM:SS:hh (24-hour) and calendar in YY-MM-DD-dd format. Packaged in a standard 8-pin SOIC (3.90 mm body width) for surface-mount assembly, it integrates an alarm, a watchdog timer, and a programmable square-wave output — functions that offload periodic housekeeping from the host MCU. Supply voltage spans 2 V to 5.5 V, with a separate battery-backup input requiring 2.5 V to 3.5 V. The timekeeping current draw is 100 µA maximum across the full supply range, making it suitable for battery-powered or always-on systems where the RTC must remain alive during a main power loss.

Active production, ROHS3, and industrial temp range

The part is sourced through independent distribution channels; availability and current pricing are confirmed at RFQ against the BOM quantity.

Frequently asked questions

Does the M41T81M6F include a watchdog timer or alarm?

Yes. The on-chip features include an alarm, a watchdog timer, a leap-year correction, and a programmable square-wave output. These are integrated into the RTC block and do not consume additional MCU I/O or timer resources.