Real-Time Clock (RTC) ICs

Real-time clock (RTC) ICs are used in electronic circuits to keep track of time relative to the “real” world. Maintaining accurate time is critical, especially under periods of severe system stress or when the power of the main device is off. During these times, RTC ICs must provide robust performance and will often draw power from an auxiliary battery or supercapacitor. As expected, power consumption is a key factor in most real-time clock designs, in addition to accuracy, ruggedness, and small package size. Most modern RTCs reduce the number of pins required by supporting a serial interface. We offer a wide variety of highly accurate, low-power, small-package, and MEMS (microelectromechanical systems)-based real-time clocks to suit any of your solution needs.

  • Power is reduced with ICs that contain automatic gain control (AGC) circuitry.
  • MEMs-based RTCs provide improved tolerance to shock and vibration.
  • The patented SYNC feature allows the RTC to sync with an external signal.
  • RTCs with integrated crystals or MEMS oscillators offer multiple ways to minimize board space.

Real-Time Clocks Parametric Search 

Real-Time Clock Development Boards

Serial Communications Module for Evaluation Kits


Provides bidirectional communication with 2-wire and 3-wire devices using a PC's serial port to evaluate a wide variety of ICs.

Learn more ›

Peripheral Module for ±5ppm, I2C Real-Time Clock


Interfaces the DS3231M RTC low-cost and extremely accurate RTC to any system that utilizes Pmod™-compatible expansion ports configurable for I²C.

Learn more ›

Real-Time Clock Design Resources

Application Notes

View All Application Notes ›


View All Tutorials ›

Selector Guide


Real-Time Clock Featured Products

Low-Current I²C RTC for High-ESR Crystals


RTC with an extremely low standby current, permits longer life from a power supply.

Learn more ›

Extremely Accurate I²C-Integrated RTC/TCXO/Crystal


Low-cost I²C RTC incorporates a battery input and maintains accurate timekeeping when main power is interrupted.

Learn more ›

Low-Current I²C RTC with 56-Byte NV RAM


Low-power, full BCD real-time clock and calendar compatible with any 32.768kHz crystal.

Learn more ›