DS1315EN-33+

Real Time Clock Overview

The DS1315EN-33+ is a Phantom Time Chip combining a CMOS timekeeper and nonvolatile memory controller in a 20-pin TSSOP package. It operates at +3.3V with an industrial temperature range of -40°C to +85°C. The device tracks hundredths of seconds, seconds, minutes, hours, day, date, month, and year, including automatic leap year correction valid up to 2100. Communication uses a serial bit stream pattern recognition protocol requiring 64 consecutive write cycles for access. It supports battery backup for external SRAM via VCCO output and redundant battery attachment.

Real Time Clock Feature Summary

• Phantom Clock interface using 64-bit serial pattern recognition (C5, 3A, A3, 5C) to avoid address space requirements
• Automatic leap year correction valid through the year 2100
• Nonvolatile controller with battery switching logic for external SRAM or ROM
• Industrial temperature rating (-40°C to +85°C) in 20-pin TSSOP package

Real Time Clock Applications

• Systems requiring nonvolatile timekeeping without dedicated RTC bus addresses
• High-reliability applications utilizing redundant battery inputs (BAT1/BAT2)
• Embedded controllers interfacing with external CMOS SRAM for data retention

Real Time Clock Procurement Notes

Verify component authenticity upon receipt as this is a legacy Analog Devices/Maxim Integrated product. Confirm the 20-pin TSSOP footprint matches design specifications. Check for lead-free marking on the package top surface corresponding to the '+' suffix. Ensure ESD precautions are followed during handling due to CMOS construction.

Real Time Clock Selection Notes

Select the DS1315EN-33+ when a 3.3V supply and industrial temperature range are required. The 'E' suffix indicates the 20-pin TSSOP package; use 'N' suffix variants for PDIP/SO packages if different form factors are needed. Ensure the system design accommodates the 64-bit serial handshake protocol rather than standard I2C or SPI interfaces.

Real Time Clock Part Context

This part belongs to the DS1315 family of Phantom Time Chips. The EN-33+ designation specifies the Industrial temperature grade (-40°C to +85°C), 3.3V operation, and 20-pin TSSOP packaging. Other variants include the commercial grade DS1315E-33+ and different package options like the 16-pin SO or PDIP.

Real Time Clock Replacement Considerations

Direct pin-compatible replacements within the same family include the DS1315EN-5+ for 5V operation. For 3.3V systems requiring different packages, consider the DS1315S-33+ (SO) or DS1315N-33+ (PDIP). Verify that the target replacement supports the specific 64-bit phantom clock protocol.