DESCRIPTION
The Portable System Controller is a circuit, which incorporates many of the functions necessary for low power portable products integrated into one chip. The DS1670 provides a Real Time Clock, NV RAM controller, microprocessor monitor, and a 3-channel, 8-bit analog-to-digital converter. Communication with the DS1670 is established through a simple 3-wire interface.

FEATURES
■ Provides real time clock:
    − Counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap year compensation valid up to 2100
    − Power control circuitry supports system power-on from day/time alarm
■ Microprocessor monitor:
    − Halts microprocessor during power fail
    − Automatically restarts microprocessor after power failure
    − Monitors pushbutton for external override
    − Halts and resets an out of control microprocessor
■ NV RAM control:
    − Automatic battery backup and write protection to external SRAM
■ 3-channel, 8-bit analog-to-digital converter
■ Simple 3-wire interface
■ 3.3V operation