The DS1670E+ is a portable system controller in 20 pin TSSOP package. It operates at 3.3V and it incorporates many of the functions necessary for low power portable products integrated into one chip. The device provides RTC, NV RAM controller, microprocessor monitor and 3-channel, 8bit ADC. Communication with DS1670 is established through a simple 3-wire interface. The RTC provides seconds, minutes, hours, day, date, month and year information with leap year compensation valid up to 2100. The RTC also provides an alarm interrupt. This interrupt works when the DS1670 is powered by system power supply or when in battery backup operation, so the alarm can be used to wake-up system that is powered down. The microprocessor monitor circuitry of DS1670 provides three basic functions. First, a precision temperature compensated reference and comparator circuit monitors the status of VCC. The second function is pushbutton reset control and third function is a watchdog timer.
● Supply voltage range from 2.97V to 3.63V
● Operating temperature range from 0°C to 70°C
● UL recognized
● 300nA time keeping current, 0.75mA active supply current and 100µA standby current
● Power control circuitry supports system power-on from day/time alarm
● Halts microprocessor during power fail & automatically restarts microprocessor after power failure
● Monitors pushbutton for external override
● Halts and resets an out of control microprocessor
● Automatic battery back-up and write protection to external SRAM
● VCC trip point of 2.88V and reset active time of 250ms