M41T93ZMY6F

M41T93ZMY6F
Serial SPI bus real-time clock (RTC) with battery switchover, embedded crystal 32768 Hz, SOX18, STM, RoHS

---

The M41T93ZMY6F is a low-power serial SPI bus real-time clock (RTC) with a built-in 32.768 kHz oscillator. Eight bytes of the register map are used for the clock/calendar function and are configured in binary coded decimal (BCD) format. An additional 17 bytes of the register map provide status/control of the two alarms, watchdog, 8-bit counter, and square wave functions. An additional seven bytes are made available as user SRAM.

Addresses and data are transferred serially via a serial SPI bus-compatible interface. The built-in address register is incremented automatically after each WRITE or READ data byte. The M41T93ZMY6F has a 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 button battery when a power failure occurs.

Features:

• Ultra-low battery supply current of 365 nA
• Factory calibrated accuracy ±5 ppm typical after 2 reflows (SOX18) (much better accuracies are 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: V_CC= 2.38 V to 5.50 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 2^ndprogrammable 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 supercapacitor backup
• Operating temperature of –40 °C to +85 °C
• Package: 18-lead embedded crystal SOIC

---