ST's serial real-time clocks range from ultralow power devices for portable applications to high-accuracy parts with analog calibration. The product family also offers factory calibrated RTC modules with an embedded crystal.
High-end RTCs offer no compromise on performance and functionalities. They combine low standby current and high-end features such as tamper detection with timestamp and watchdog SRAM supervisor functions to meet all high-end applications requirements.
Battery with crystal optionST's removable/replaceable SNAPHAT battery top contains a lithium coin-cell battery and a 32-kHz crystal. It is compatible with all ST's serial and parallel-interface real-time clocks in surface-mount SOH-28 and SOH-44 packages.
The SNAPHAT top is designed to be "snapped on" after the SOIC is surface-mounted on the PC board, preventing the battery and crystal from being exposed to the high temperatures of the surface mount process.
To evaluate the battery consumption capacity and lifetime, visit the real-time clock battery life calculation webpage.
C code examples for interfacing with our serial RTCs are also available.
Applications
Product types
High-end RTCs offer no compromise on performance and features combining low standby current and high-end features such as, tamper detection with timestamp and watchdog SRAM supervisor functions to meet all high-end applications requirements.
For high accuracy timekeeping, the crystal product line is the perfect choice thanks to the factory calibrated oscillator which is down to +/-5 ppm. The crystal embedded in the package further improves the oscillator noise immunity, which is not impacted by PCB traces connections.
In addition, SNAPHAT top, which embeds both crystal and the battery, together with SOH-28 packaged RTCs delivers higher benefits.
The basic product line offers industry standard SO-8 package for ease-of-use and compatibility.
Discover our portfolio of Serial Interface RTC
Benefits
- High accuracy timekeeping down to +/- 5 ppm
- High-noise immunity thanks to the embedded crystal options
- Industry standard package for high compatibility
- SRAM supervising functions
- Tamper detection with timestamp
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Real-time clock for demanding wearable devices
ST’s M41T62LC6F real-time clock is the perfect match for wearable devices when size, weight, and power-efficiency matters.
It offers a very low frequency error at 25 °C which equates to about 5 seconds per month, an ultra-low power consumption of 350 nA in standby, and comes in an ultra-small 1.5 x 3.2 mm package with an embedded crystal oscillator.
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- M41ST85W 3.0/3.3 V I²C combination real-time clock, NVRAM supervisor and microprocessor supervisor
- M41T81S Serial real-time clock (RTC) with alarm
- M41T00S Serial real-time clock (RTC)
- M41T01 Serial real-time clock (RTC) with built-in battery switchover circuit
- M41T62 Low-power serial real-time clock (RTC) with alarm