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