M48T08Y,

The M48T08/18/08Y TIMEKEEPER^® RAM is an 8K x 8 non-volatile static RAM and real time clock which is pin and functional compatible with the DS1643. The monolithic chip is available in two special packages to provide a highly integrated battery backed-up memory and real time clock so-lution.

The M48T08/18/08Y is a non-volatile pin and func-tion equivalent to any JEDEC standard 8K x 8 SRAM. It also easily fits into many ROM, EPROM,and EEPROM sockets, providing the non-volatility of PROMs without any requirement for special WRITE timing or limitations on the number of WRITEs that can be performed.

The 28-pin, 600mil DIP CAPHAT™ houses the M48T08/18/08Y silicon with a quartz crystal and a long- life lithium button cell in a single package.

The 28-pin, 330mil SOIC provides sockets with gold plated contacts at both ends for direct con-nection to a separate SNAPHAT® housing con-taining the battery and crystal. The unique design allows the SNAPHAT battery package to be mounted on top of the SOIC package after the completion of the surface mount process. Inser-tion of the SNAPHAT housing after reflow pre-vents potential battery and crystal damage due to the high temperatures required for device surface-mounting. The SNAPHAT housing is keyed to pre- vent reverse insertion.

The SOIC and battery/crystal packages are shipped separately in plastic anti-static tubes or in Tape & Reel form. For the 28 lead SOIC, the bat-tery/crystal package (e.g., SNAPHAT) part num-ber is "M4T28-BR12SH" or "M4T32-BR12SH"(see Table 17, page 24).