M48T58

Note: 1. For DIP package: Soldering temperature not to exceed 260°C for 10 seconds (total thermal
              budget not to exceed 150 for longer than 30 seconds).
          2. For SO package: Reflow at peak temperature of 215 to 225 for < 60 seconds (total thermal
              budget not to exceed 180 for between 90 to 120 seconds).

CAUTION: Negative undershoots below 0.3V are not allowed on any pin while in the Battery Back-up mode.
CAUTION: Do NOT wave solder SOIC to avoid damaging SNAPHAT sockets.

The M48T58/Y TIMEKEEPER^® RAM is a 8Kb x 8 non-volatile static RAM and real time clock. The monolithic chip is available in two special packages to provide a highly integrated battery backed-up memory and real time clock solution.

The M48T58/Y is a non-volatile pin and function equivalent to any JEDEC standard 8Kb x 8 SRAM. M48T58/Y 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 M48T58/Y 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 connection to a separate SNAPHAT^® housing containing the battery and crystal. The unique design allows the SNAPHAT M48T58/Y battery package to be mounted on top of the SOIC package after the completion of the surface mount process. Insertion of the SNAPHAT housing after reflow prevents potential battery and crystal damage due to the high temperatures required for device surfacemounting. The SNAPHAT housing is keyed to prevent reverse insertion. The SOIC and battery/crystal packages of M48T58/Y are shipped separately in plastic antistatic tubes or in Tape & Reel form.

For the 28-lead SOIC M48T58/Y, the battery/crystal package (e.g., SNAPHAT) part number is "M4T28- BR12SH" (see Table 13, page 21).