M41ST87WMX6TR

Real Time Clock Overview

The M41ST87WMX6TR is a serial real-time clock (RTC) and NVRAM supervisor manufactured by STMicroelectronics. It integrates a low-power static CMOS SRAM organized as 160 bytes by 8 bits, with 128 bytes available for user data. The device includes an internal 32.768 kHz oscillator and supports I²C bus communication at frequencies up to 400 kHz. Operating voltage ranges from 2.7 V to 3.6 V, with a maximum current consumption of 0.5 mA. It features automatic battery switchover, tamper detection, and watchdog timer functions, suitable for industrial applications within a temperature range of -40°C to +85°C.

Real Time Clock Feature Summary

• Integrated 128-byte non-volatile RAM and 160-byte total SRAM capacity
• I²C serial interface supporting 400 kHz clock frequency
• Automatic power-fail detection and battery backup switching
• Built-in tamper detection and programmable watchdog timer

Real Time Clock Applications

• Smart metering systems requiring secure timekeeping
• Industrial control units needing reliable RTC supervision
• Embedded devices with limited power supply constraints

Real Time Clock Procurement Notes

Verify the specific suffix MX6TR indicates tape-and-reel packaging containing 1000 units per reel. Confirm RoHS compliance status and lead times directly with authorized distributors or STMicroelectronics sales representatives, as availability may vary by region and production cycle.

Real Time Clock Selection Notes

Select this component when a combined RTC and NVRAM supervisor is required in a single package. Ensure the system design accommodates the 28-SOIC surface-mount footprint. Verify that the I²C bus voltage levels are compatible with the 2.7 V to 3.6 V operating range before integration into the main processor architecture.

Real Time Clock Part Context

This part belongs to the M41ST87W series of secure serial RTCs. It shares functional similarities with the M41ST87YMX6 but differs in packaging and specific feature sets such as tamper detection capabilities. The TR suffix specifically denotes the reel packaging format used for automated surface-mount assembly processes.

Real Time Clock Replacement Considerations

The M41ST87YMX6 is a related variant within the same family; however, it is marked as not recommended for new designs. Direct pin-to-pin replacements should be verified against official STMicroelectronics substitution guides to ensure compatibility with voltage levels and feature sets.