DALLAS Semiconductor, represented by Arrow Electronics , has introduced the DS1374 2-wire serial real-time clock (RTC).
The DS1374 combines a 32-bit binary counter, watchdog, period alarm, programmable square-wave output, and power-on reset.
The elapsed time counter's 32-bit binary counter increments once per second, and can be used to derive time of day, week, month, and year by using a software algorithm.
The DS1374 monitors Vcc and when a power-fail occurs, it write-protects the internal registers, resets the processor, and switches to backup power to prevent data corruption.
In low-power mode, the oscillator maintains timekeeping down to 1.3V, consuming less than 1 microamp of current. When Vcc returns to nominal conditions, the DS1374 holds the processor in reset for 250ms while operating conditions stabilise.
An optional trickle-charging circuit backs up the DS1374 with a super cap or rechargeable battery. Additionally, the reset pin is monitored as a pushbutton input for externally generating a reset. Address and data are transferred serially through a 2-wire serial bus.
The DS1374 operates over the extended-industrial temperature range (-40°C to +85°C) and is available in a 10-pin microSOP package.