DS1244P

19-6077; Rev 11/11 www.maxim-ic.com DS1244/DS1244P 256K NV SRAM with Phantom Clock FEATURES  Real-Time Clock (RTC) Keeps Track of Hundredths of Seconds, Minutes, Hours, Days, Date of the Month, Months, and Years  32K 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  Automatic Leap Year Compensation Valid Up to 2100  Full 10% Operating Range  Over 10 Years of Data Retention in the Absence of Power  Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time  DIP Module Only  Standard 28-Pin JEDEC Pinout  PowerCap Module Board Only – Surface Mountable Package for Direct Connection to PowerCap Containing Battery and Crystal – Replaceable Battery (PowerCap) – Pin-for-Pin Compatible with DS1248P and DS1251P  Underwriters Laboratories (UL) Recognized PIN CONFIGURATIONS TOP VIEW A14/RST A12 A7 A6 A5 A4 A3 A2 A1 A0 DQ0 DQ1 DQ2 GND 1 2 DS1244 28 27 3 26 4 25 5 24 6 23 7 22 8 21 9 20 10 19 11 18 12 17 13 16 14 15 EDIP Module (740 mils) VCC WE A13 A8 A9 A11 OE A10 CE DQ7 DQ6 DQ5 DQ4 DQ3 RST N.C. N.C. N.C. VCC WE OE CE DQ7 DQ6 DQ5 DQ4 DQ3 DQ2 DQ1 DQ0 GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 DS1244P X1 GND VBAT X2 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 PowerCap Module (Uses DS9034PCX+ PowerCap) N.C. N.C. A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A...