DESCRIPTION

The DS1680 incorporates many functions necessary for low-power portable products, providing an RTC, NV RAM controller, microprocessor monitor, power-fail warning, 10-bit ADC, and a touch-screen controller in one chip.

FEATURES

■ Real-time clock (RTC)

- Counts seconds, minutes, hours, date, 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

■ 1.25V threshold detector for power-fail warning

■ 10-bit analog-to-digital converter (ADC)

- Monotonic with no missing codes

■ Four-wire analog resistive touch-screen interface