DS1338C-33

Real Time Clock Overview

The DS1338C-33 is a low-power serial real-time clock (RTC) and calendar integrated with 56 bytes of non-volatile static RAM. Manufactured by Analog Devices Inc./Maxim Integrated, this component utilizes an I2C interface for data transfer in binary-coded decimal format. It features an integrated crystal oscillator, eliminating the need for external timing components. The device supports 12-hour or 24-hour time formats and automatically adjusts for leap years through 2100. Operating within a supply voltage range of 3V to 5.5V, it includes automatic power-fail detection and switching circuitry to maintain timekeeping during main power loss.

Real Time Clock Feature Summary

• Integrated 32.768kHz crystal oscillator reduces external component count
• 56-byte battery-backed NV SRAM with unlimited write cycles
• Automatic power-fail detect and switch circuitry
• Leap-year compensation valid up to the year 2100

Real Time Clock Applications

• GPS handheld devices
• POS terminals
• Set-top boxes and digital recording equipment
• Network appliances and servers
• Utility meters and vending machines

Real Time Clock Procurement Notes

Verify the specific suffix 'C' indicates the package variant containing the integrated crystal. Confirm the operating temperature range matches the application requirements, typically -40°C to +85°C. Ensure the I2C bus speed compatibility with the host microcontroller before integration into the design.

Real Time Clock Selection Notes

Select the DS1338C-33 when board space is limited due to the integrated crystal option. Compare current consumption specifications against other RTCs if battery life is critical. Verify that the 16-pin SOIC package dimensions fit the PCB footprint constraints. Check for alternative packages like TSSOP if smaller surface-mount area is required.

Real Time Clock Part Context

This part belongs to the DS1338 family of serial RTCs. The 'C' designation specifically denotes the version with the integrated crystal, distinguishing it from standard versions requiring external oscillators. It serves as a direct replacement for older discrete RTC solutions in compact consumer electronics designs.

Real Time Clock Replacement Considerations

The DS1338Z-3+T&R offers similar functionality but may differ in package type or integrated features. Verify pinout compatibility and register mapping before substituting. The DS1339 series provides additional features such as alarms and trickle chargers.