STMicroelectronics M48T35Y-70MH1F, Real Time Clock, 28-Pin DIP

The STMicroelectronics Static RAM features a monolithic chip which is available in two special packages to provide a highly integrated battery backed memory and real time clock solution. It is a non volatile pin and function equivalent to any JEDEC standard 32 Kb 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.

Self contained battery and crystal in the CAPHAT DIP package
Frequency test output for real time clock
Automatic power fail chip deselect and write protection