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Manufacturer Part #


M41T93 Series 5.5V Serial SPI Bus Real-Time Clock with Battery Switchover-SOX-18

ECAD Model:
Mfr. Name: STMicroelectronics
Standard Pkg:
Product Variant Information section
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Product Specification Section
Technical Attributes
Attributes Table
Interface: SPI
Non-Volatile Memory Size: 7B
Supply Voltage-Nom: 3V to 5.5V
Temperature Grade: Industrial
Package Style:  SOX-18
Mounting Method: Surface Mount
Features & Applications
The M41T93SMY6F is a low power Serial SPI Bus Real-Time Clock (RTC) with a built-in 32.768 KHz oscillator, available in SOX-18 package.

It has built-in power sense circuit which detects power failures and automatically switches to the battery supply when a power failure occurs. The energy needed to sustain the clock operations can be supplied by a small lithium.


  • Ultra-low battery supply current of 365 nA
  • Factory calibrated accuracy ±5 ppm guaranteed after 2 reflows (SOX18)
    • Much better accuracies achievable using built-in programmable analog and digital calibration circuits
  • 2.0 V to 5.5 V clock operating voltage
  • Counters for tenths/hundredths of seconds, seconds, minutes, hours, day, date, month, year, and century
  • Automatic switchover and reset output circuitry (fixed reference)
    • M41T93S: VCC = 3.0 V to 5.5 V (2.85 V ≤ VRST ≤ 3.00 V)
  • Compatible with SPI bus serial interface (supports SPI mode 0 [CPOL = 0, CPHA = 0])
  • Programmable alarm with interrupt function (valid even during battery backup mode)
  • Optional 2nd programmable alarm available
  • Square wave output (defaults to 32 KHz on power-up) RESET (RST) output
  • Watchdog timer
  • Programmable 8-bit counter/timer
  • 7 bytes of battery-backed user SRAM
  • Battery low flag
  • Low operating current of 80 μA
  • Oscillator stop detection
  • Battery or SuperCap™ backup
  • Operating temperature of –40 °C to +85 °C
  • Package options include:
  • a 16-lead QFN or an 18-lead embedded crystal SOIC
  • RoHS compliance: lead-free components are compliant with the RoHS directive
Pricing Section
Global Stock:
On Order:
Factory Stock:Factory Stock:
Factory Lead Time:
40 Weeks
Minimum Order:
Multiple Of:
Web Price
Product Variant Information section