The ISL1221 is a low power real time clock from Intersil with event detect and time stamp function, timing and crystal compensation, clock/calendar, power fail indicator, periodic or polled alarm, intelligent battery backup switching with separate FOUT output and 2 Bytes of battery-backed user SRAM.
The ISL1221 is a low‑power real‑time clock and calendar IC that includes event detection, tamper detection, and a 2‑byte battery‑backed SRAM. It operates from 2.7 V to 5.5 V and can run on a backup battery or super‑capacitor down to 1.8 V.
Typical applications include utility meters, set‑top boxes, POS equipment, network routers, cellular infrastructure, vending machines, security systems and automotive devices. The device uses an external 32.768 kHz crystal and provides a selectable 15‑frequency output pin.
| Battery‑backed SRAM | 2 Bytes |
|---|---|
| Frequency Output Pin (FOUT) | 15 selectable frequencies |
| Package | 10‑lead MSOP (Mini Small Outline Plastic) |
The ISL1221 includes 2 bytes of battery‑backed SRAM.
An external 32.768 kHz crystal is used.