V3021 - Real Time Clocks - IC

Ultra Low Power 1-Bit 32kHz RTC, 0.8uA standby current, up to +125°C

General Description

The V3021 is a low power CMOS real time clock. Data is transmitted serially as 4 address bits and 8 data bits, over one line of a standard parallel data bus. The device is accessed by chip select (/CS) with read and write control timing provided by either /RD and /WR pulse (Intel CPU) or /DS with advanced R/W (Motorola CPU). Data can also be transmitted over a conventional 3 wire serial interface having CLK, data I/O and strobe. The V3021 has no busy states and there is no danger of a clock update while accessing. Supply current is typically 800nA at VDD = 3.0V. Battery operation is supported by complete functionality down to 2.0V. The oscillator stability is typically 0.3 ppm/V.

Solutions

• Utility meters
• Battery operated and portable equipment
• Consumer electronics
• White/brown goods
• Pay phones
• Cash registers
• Personal computers
• Programmable controller systems
• Data loggers
• Automotive electronics

• Supply current typically 800nA at 3V
• 50ns access time with 50pF load capacitance
• Fully operational from 2.0V to 5.5V
• No busy states or danger of a clock update while accessing
• Serial communication on one line of a standard parallel data bus or over a conventional 3 wire serial interface
• Interface compatible with both Intel and Motorola
• Seconds, minutes, hours, day of month, month, year, week day and week number in BCD format
• Leap year and week number correction
• Time set lock mode to prevent unauthorized setting of the current time or date
• Oscillator stability 0.3 ppm/volt
• No external capacitor needed
• Frequency measurement and test modes
• Temperature range - 40 to +85°C
• On request extented temperature range -40 to +125°C
• Packages DIP8 and SO8