| Image | Part Number | Manufacturer | Description | Series | Operating Temperature | Features | Packaging | Mounting Type | RoHS Status | Manufacturer Part Number | Type | Voltage - Supply |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| X1228S14IZ | Intersil | IC RTC CLK/CALENDAR I2C 14-SOIC | - | -40°C ~ 85°C | Alarm, Leap Year, Supervisor, Watchdog Timer | Tube | Surface Mount | - | - | Clock/Calendar | 2.7 V ~ 5.5 V | |
| DS1308U-3+ | Maxim Integrated | IC RTC CLK/CALENDAR I2C 8-UMAX | - | -40°C ~ 85°C | Leap Year, NVSRAM, Square Wave Output | Tube | Surface Mount | - | - | Clock/Calendar | 2.7 V ~ 5.5 V | |
| M48T59Y-70MH1E | STMicroelectronics | IC RTC CLK/CALENDAR PAR 28SOH | Timekeeper® | 0°C ~ 70°C | Alarm, Leap Year, Watchdog Timer | Tube | Surface Mount | - | - | Clock/Calendar | 4.5 V ~ 5.5 V | |
| PCF8563T/5,518 | NXP Semiconductors / Freescale | IC RTC CLK/CALENDAR I2C 8-SOIC | - | -40°C ~ 85°C | Alarm, Leap Year, Watchdog Timer | Original-Reel® | Surface Mount | - | - | Clock/Calendar | 1.8 V ~ 5.5 V | |
| X1286A8IT1 | Intersil | IC RTC CLK/CALENDAR I2C 8-SOIC | - | -40°C ~ 85°C | Alarm, Leap Year, Supervisor, Watchdog Timer | Tape & Reel (TR) | Surface Mount | - | - | Clock/Calendar | 2.7 V ~ 5.5 V | |
| RX-8035LC:AC0 PURE SN | Epson | IC TRC CLK/CALENDAR | - | - | - | - | - | - | - | - | - | |
| DS1307N+ | Maxim Integrated | IC RTC CLK/CALENDAR I2C 8-DIP | - | -40°C ~ 85°C | Leap Year, NVSRAM, Square Wave Output | Tube | Through Hole | - | - | Clock/Calendar | 4.5 V ~ 5.5 V | |
| DS1315S-33+T&R | Maxim Integrated | IC RTC PHANTOM PAR 16-SOIC | - | 0°C ~ 70°C | Leap Year | Tape & Reel (TR) | Surface Mount | - | - | Phantom Time Chip | 3 V ~ 3.6 V | |
| MAX6917EO33+T | Maxim Integrated | IC RTC I2C COMPAT 20-QSOP | - | -40°C ~ 85°C | - | Tape & Reel (TR) | Surface Mount | - | - | Clock/Calendar/Supervisor | 3 V ~ 3.6 V | |
| DS1742-100IND | Maxim Integrated | IC RTC CLK/CALENDAR PAR 24-EDIP | - | -40°C ~ 85°C | Leap Year, NVSRAM, Y2K | Tube | Through Hole | - | - | Clock/Calendar | 4.5 V ~ 5.5 V |
Real-time clocks (RTCs) are electronic devices that keep track of the current time and date with high accuracy, independent of external power sources. They typically include a built-in crystal oscillator and a battery backup to ensure continuous timekeeping even when the main power is off. RTCs are commonly used in applications such as consumer electronics, industrial automation, medical devices, and automotive systems where precise timekeeping is essential for scheduling tasks, logging events, and time-stamping data.