GN Semic GN1303

The GN1303 trickle charge timekeeping chip incorporates a real-time clock/calendar and 31 bytes of static RAM, communicating with a microprocessor via a simple serial interface. The real-time clock/calendar provides year, month, date, hour, minute, and second information, with automatic end-of-month adjustment for months with fewer than 31 days, as well as leap year correction. With an AM/PM indicator, the clock can operate in either 12-hour or 24-hour format. In addition to timekeeping functions, the following features are included: dual-pin primary and backup power supply, programmable trickle charger VCC1, and an additional 7-byte scratch pad register.

• Real-time clock computing year, month, day, hour, minute, second, and day-of-week through year 2100 with leap-year compensation.
• 31 x 8-bit general-purpose scratchpad RAM.
• Wide operating voltage range: 2.0V to 5.5V.
• Operating current less than 300nA at 2.0V.
• Single-byte or multi-byte (burst mode) data transfer for reading/writing clock or RAM data.
• Simple 3-wire interface.
• TTL-compatible.
• Operating temperature: -20°C to +85°C.
• Compatible with DS1202/DS1302.

• Telephone
• Fax
• Portable instruments
• Battery-powered instrumentation