V3020SO8A+

Real Time Clock Overview

The V3020SO8A+ is an ultra-low power CMOS real-time clock (RTC) manufactured by EM Microelectronic. It provides seconds, minutes, hours, day of month, month, year, weekday, and week number in BCD format with leap year correction. The device operates from a supply voltage of 1.2V to 5.5V with typical static current of 390 nA at 3V. It supports Intel and Motorola bus timing or a 3-wire serial interface via a single I/O line. The oscillator stability is 0.3 ppm/V, and it requires no external capacitor.

Real Time Clock Feature Summary

• Ultra-low power consumption: typically 390 nA at 3V
• Wide operating voltage range: 1.2V to 5.5V
• Compatible with Intel (RD/WR pulse) and Motorola (DS/R/W) interfaces
• Includes time set lock mode and frequency measurement capability

Real Time Clock Applications

• Utility meters
• Battery operated and portable equipment
• Consumer electronics
• White/brown goods
• Automotive systems

Real Time Clock Procurement Notes

Verify the package marking for lot number and date code suffixes. Confirm the specific temperature grade required, as standard (-40°C to +85°C) and extended (-40°C to +125°C) versions exist. Ensure the delivery form matches system requirements, as the 'A+' suffix indicates stick packaging while 'B+' indicates tape and reel.

Real Time Clock Selection Notes

Select the V3020SO8A+ for applications requiring low standby current and simple serial communication without busy states. Choose the extended temperature version (XSO8) if operation above +85°C is necessary. Ensure the microprocessor interface timing aligns with either Intel or Motorola standards, or utilize the 3-wire serial mode for simplified connections.

Real Time Clock Part Context

The V3020 is part of the EM3020 family of RTCs. It is pin-compatible with the V3021 model. The SO8 package variant is available in both stick and tape & reel forms, distinguished by the ordering suffix A+ or B+. The device integrates a 32 kHz crystal oscillator circuit internally.

Real Time Clock Replacement Considerations

Public confirmed substitute part numbers are not provided in the source material.

Real Time Clock FAQ

How is the V3020 initialized after a system reset?

Software must initialize the V3020 by executing 8 microprocessor reads to ensure the internal serial buffer is waiting for the address bit A0.

What is the function of the Time Set Lock bit?

When set, the Time Set Lock bit disables the Copy_RAM_to_clock command, preventing unauthorized overwriting of the current time and date.

Does the V3020 generate interrupts?

No, the V3020 does not generate interrupts. Software must poll the status bits to detect changes in time or date parameters.