These devices are detachable lithium power sources housed in special top called SNAPHAT? and are compatible with ST’s nonvolatile TIMEKEEPER? surface-mount SOIC (MH) package. The SNAPHAT top contains both the battery and crystal and is designed to be "snapped on" after the SOIC is surface mounted on the PC board. Thus the two piece solution prevents the battery and crystal from being exposed to the high temperatures of the surface mount process.
To make designing with real-time clock ICs even easier, ST offers a simulator:
- Battery life calculation allows to evaluate the battery capacity consumption and lifetime of ST's real-time clock ICs