Achieving record low power consumption, typically drawing only 0.8µA with fully operational temperature compensation, the M41TC8025 single-chip real-time clock helps reduce operating costs for electronic utility meters and can extend the lifetime of battery-powered equipment.
Temperature compensation guarantees accuracy to within 2.5 minutes per year (±5 ppm) over the entire specified temperature range from -40ºC to +85ºC, allowing precise time stamping and tariff switching in metering applications across seasons and in various climates.
ST’s M41TC8025 single-chip real-time clock also offers superior corrosion resistance, as tests with a lead customer have revealed. The customer, a producer of electronic utility meters for use outdoors in harsh environments such as coastal regions, performed corrosion testing and found that ST’s new single-chip real-time clock outperforms functionally equivalent devices, owing to its high-quality package design and materials.
The M41TC8025 generates accurate date and time information in seconds, minutes, hours, day-of-week, date (day of month), month and year, and helps simplify system design by providing extra integrated functions including an alarm, fixed-cycle timer, time-update interrupt, and programmable frequency outputs.
The device integrates a temperature-compensated 32768 Hz crystal oscillator as precision timing reference, which helps minimise component count and simplify system hardware design.
Key features of ST’s M41TC8025 single-chip real-time clock:
- 0.8 μA typical current at 3.0V supply voltage
- Guaranteed accuracy over temperature:
- ±5.0 ppm max from -40 to 85ºC (c. 2.5 minutes per year)
- ±3.8 ppm max from 0 to 50ºC (better than 2 minutes per year)
- Embedded high-stability 32 KHz temperature-compensated crystal oscillator
- Time-of-day alarm (with interrupt)
- Fixed-cycle timer-interrupt function
- Time-update interrupt function
- Programmable frequency output (1 Hz, 1024 Hz and 32768 Hz)
- 400kHz I2C interface