This document describes the features and characteristics of the xicor 2-Wire ™ RTC Real Time Clock/Calendar. It has clock/calendar, 2 polled alarms, oscillator compensation, battery switch or super capacitor input, 2-Wire ™ interface, low power CMOS etc.
The X1205 Real Time Clock/Calendar provides time‑keeping with separate registers for seconds, minutes, hours, date, month, year and day‑of‑week, plus automatic leap‑year correction through 2099. It features two non‑volatile polled alarms, on‑chip oscillator compensation with a 64‑position digitally controlled trim capacitor, and a backup power input (V_BACK) for battery or super‑capacitor operation.
Communication uses a 2‑Wire™ (I²C‑compatible) interface at up to 400 kHz, with active‑low open‑drain pins for SCL, SDA and IRQ. The device operates from 2.7 V to 5.5 V (clock/calendar down to 1.8 V in standby) and draws only 1.25 µA typical current, making it suitable for utility meters, HVAC, audio/video equipment, networking gear, and other industrial or consumer applications.
| Operating Current | 1.25 µA (typical) |
|---|---|
| Supply Voltage | 2.7 V to 5.5 V |
| Standby Voltage | 1.8 V (clock/calendar portion) |
| Data Transfer Rate | 400 kHz (2‑Wire™) |
| Package Options | 8‑Lead SOIC, 8‑Lead TSSOP |
The X1205 provides two non‑volatile polled alarms that can be set to match any clock/calendar value.
V_BACK supplies backup power from a battery or super‑capacitor, allowing the device to retain time when V_CC is lost.