●Description
●The M41T93 is a low power Serial SPI Bus Real Time Clock with a built-in 32.768kHz oscillator (external crystal-controlled for the QFN16 package, and embedded crystal for the SOX18 package). Eight bytes of the Register Map (see Table 3 on page 18) 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.
●Features
●■ Ultra-low battery supply current of 365nA
●■ Factory calibrated accuracy ±5PPM guaranteed after 2 reflows (SOX18)
● – Much better accuracies achievable using built-in programmable analog and digital calibration circuits
●■ 2.0V to 5.5V clock operating voltage
●■ Counters for tenths/hundredths of seconds, seconds, minutes, hours, day, date, month, year, and century
●■ Automatic switch-over and reset output circuitry (fixed reference)
● –M41T93S: VCC= 3.0V to 5.5V (2.85V≤VRST ≤ 3.00V)
● –M41T93R: VCC= 2.7V to 5.5V (2.55V≤VRST ≤ 2.70V)
● –M41T93Z: VCC= 2.38V to 5.50V (2.25V≤VRST≤2.38V)
●■ Compatible with SPI busserial interface (positive clock SPI modes)
●■ Programmable alarm with interrupt function (valid even during battery back-up mode)
●■ Optional 2nd programmable alarm available
●■ Square wave output (defaults to 32kHz on power-up)
●■ RESET (RST) output
●■ Watchdog timer
●■ Programmable 8-bit counter/timer
●■ 7 bytes of battery-backed user SRAM
●■ Battery low flag
●■ Power-down timestamp (HT bit)
●■ Low operating current of 80µA
●■ Oscillator stop detection
●■ Battery or Super-cap™ back-up
●■ 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
