
Nippon Precision Circuits
OVERVIEW
The SM8580AM is a real-time clock IC based on a 32.768 kHz crystal oscillator, which features a 4-bit paral lel interface for communication with an external microcontroller.
It comprises second-counter to year-counter clock and calendar circuits that feature automatic leap-year adjust ment up to year 2099, alarm and timer interrupt functions, clock counter change detect functions, ±30-second correction function, time error correction function, and built-in temperature sensor.
The 4-bit parallel interface is compatible with general-purpose SRAM over a high-speed bus.
FEATURES
■ High-speed bus 4-bit parallel interface
■ Date, day, hour, minute, and second-counter pre settable alarm interrupt
■ 1/4096 seconds to 255 minutes presettable interval timer interrupt function
■ 2 software-maskable alarm and timer interrupt outputs
■ Clock counter change detect functions
■ 4-digit western calendar display
■ Automatic leap year correction up to year 2099
■ ±30-second adjust function
■ −195 to +192ppm time error correction range
■ Built-in temperature sensor (analog voltage output)
■ 2.4 to 5.5V interface voltage range
■ 1.6 to 5.5V clock voltage range
■ 0.6µA/3V (typ) current consumption