Space-saving real-time clocks

A family of real-time clocks (RTCs) developed by Intersil integrates 4kbits of electronically erasable programmable read only memory (EEPROM) (2.0 million write cycles) and CPU supervisory functions. The RTCs provide crystal frequency trimming, which is critical for clock accuracy and allows the use of low-cost crystal.

The ISL12026/27/28/29 family features low power dissipation (800nA battery supply current) in battery-backup mode, enabling the use of small batteries or super caps for backup, a key in handheld applications. The ISL12027, ISL12028, and ISL12029 also integrate CPU supervisory functions, which saves board space because power-on reset and watchdogtimer discrete devices are no longer needed.