M41T94MH6F

Real Time Clock Overview

The M41T94MH6F is a serial real-time clock (RTC) manufactured by STMicroelectronics, belonging to the M41T94M series. It features a 28-pin SOH package and operates within a supply voltage range of 2.7 V to 5.5 V. The device integrates 44 bytes of non-volatile RAM (NVRAM) and utilizes an SPI interface for data transfer. It supports binary date formats and includes automatic calendar corrections for leap years until 2100. The component functions across a temperature range of -40°C to +85°C.

Real Time Clock Feature Summary

• Integrated power sense circuit with automatic battery backup switching
• Built-in watchdog timer and programmable square wave output
• Automatic calendar correction for months up to year 2100
• Two debounced reset inputs (RSTIN1, RSTIN2)

Real Time Clock Applications

• Industrial control systems requiring precise timekeeping
• Embedded devices needing non-volatile time-of-day tracking
• Systems utilizing SPI interfaces for low pin-count RTC integration

Real Time Clock Procurement Notes

Verify the specific suffix MH6F against official STMicroelectronics documentation to confirm package type and tape/reel specifications. Ensure compatibility with system voltage levels between 2.7 V and 5.5 V. Confirm that the SNAPHAT package variant matches the required crystal and battery integration needs for the target application design.

Real Time Clock Selection Notes

Select this model when an SPI interface is preferred over I2C for the RTC function. The 28-lead SOIC SNAPHAT package integrates the crystal and battery contacts, reducing external component count compared to the 16-lead SOIC version. Verify that the 44-byte NVRAM capacity meets the data storage requirements alongside the clock/calendar registers.

Real Time Clock Part Context

This part belongs to the M41T94M family of serial real-time clocks. The M41T94 series distinguishes itself by offering integrated power management features and multiple package options, including versions with integrated crystal/battery sockets (SNAPHAT) and standard surface-mount packages.

Real Time Clock Replacement Considerations

Direct substitutes include other variants within the M41T94 series, such as M41T94MQ6F, though package differences (SO-16 vs SOH-28) must be evaluated. Cross-family replacements require verification of SPI compatibility and voltage ranges.