DS1251Y - Dallas Semiconducotr

DS1251Y 4096K NV SRAM with Phantom Clock

A0–A18 CE GND DQ0–DQ7 VCC WE OE RST – – – – – – – – Address Inputs Chip Enable Ground Data In/Data Out Power (+5V) Write Enable Output Enable Reset • Available in 120 ns and 150 ns access time ORDERING INFORMATION DS1251Y–120 DS1251Y–150 120 ns access 150 ns access DESCRIPTION The DS1251Y 4096K NV SRAM with Phantom Clock is a fully static nonvolatile RAM .

Features

PIN ASSIGNMENT A18/RST A16 A14 A12 A7 A6 A5 A4 A3 A2 A1 A0 DQ0 DQ1 DQ2 GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 VCC A15 A17 WE A13 A8 A9 A11 OE A10 CE DQ7 DQ6 DQ5 DQ4 DQ3
• Real time clock keeps track of hundredths of seconds, minutes, hours, days, date of the month, months, and years
• 512K x 8 NV SRAM directly replaces volatile static RAM or EEPROM
• Embedded lithium energy cell maintains calendar operation and retains RAM data
• Watch function is transparent to RAM operation
• Month and year determine the number of days in each month; v.