R2051L01-E2

Real Time Clock Overview

The R2051L01-E2 is a CMOS real-time clock IC featuring a 2-wire I2C interface and battery backup switchover. It operates with a minimum timekeeping voltage of 0.75V (max 1.00V) and consumes 0.4µA typical current at 3V. The device includes built-in oscillation capacitors, a voltage detector with a 2.40V threshold, and supports 12/24-hour modes. It provides periodic interrupts ranging from 0.5 seconds to monthly, two alarm circuits, and a 32kHz clock output in a QFN023023-16 package.

Real Time Clock Feature Summary

• I2C Bus Interface: Connects via SCL and SDA lines supporting up to 400kHz fast mode.
• Battery Backup Switchover: Automatically switches between main power (VCC) and backup supply (VSB) based on voltage monitoring.
• Low Power Consumption: Typical timekeeping current of 0.4µA at VDD=3V.
• Integrated Oscillation Capacitors: Built-in CG and CD capacitors for quartz crystal connection.

Real Time Clock Applications

• Portable electronic devices requiring precise timekeeping with low power consumption.
• Systems utilizing primary or secondary batteries for backup power.
• Applications needing automatic switchover between main and backup power supplies.
• Devices requiring periodic interrupt signals for CPU synchronization.

Real Time Clock Procurement Notes

Verify the specific suffix E2 corresponds to the taping type designation as per the manufacturer's selection guide. Confirm that the QFN023023-16 package dimensions align with the PCB footprint requirements. Ensure compatibility with the 2.40V typical detector threshold for the intended power supply design.

Real Time Clock Selection Notes

Select this model for applications requiring the QFN023023-16 package format. The '01' suffix indicates a voltage detector threshold of 2.40V typical; choose '02' for 2.80V if higher thresholds are needed. Verify that the system supports the I2C protocol and can handle the open-drain outputs for SDA and INTR pins.

Real Time Clock Part Context

This component belongs to the R2051 series of 2-wire interface Real-Time Clock ICs. The series includes variants with different packages such as SSOP16 (R2051Sxx), TSSOP10G (R2051Txx), and FFP12 (R2051Kxx). The R2051Lxx variant specifically utilizes the QFN023023-16 package for high-density mounting.

Real Time Clock Replacement Considerations

Direct replacements within the same series include R2051L02-E2, which shares the QFN023023-16 package but features a 2.80V typical voltage detector threshold instead of 2.40V. Other package options like R2051S01-E2-F or R2051T01-E2-F offer similar functionality in SSOP16 and TSSOP10G formats respectively.