DS1220AD

19-5580; Rev 10/10 www.maxim-ic.com FEATURES  10 years minimum data retention in the absence of external power  Data is automatically protected during power loss  Directly replaces 2k x 8 volatile static RAM or EEPROM  Unlimited write cycles  Low-power CMOS  JEDEC standard 24-pin DIP package  Read and write access times of 100 ns  Lithium energy source is electrically disconnected to retain freshness until power is applied for the first time  Full ±10% VCC operating range (DS1220AD)  Optional ±5% VCC operating range (DS1220AB)  Optional industrial temperature range of -40°C to +85°C, designated IND DS1220AB/AD 16k Nonvolatile SRAM PIN ASSIGNMENT A7 A6 A5 A4 A3 A2 A1 A0 DQ0 DQ1 DQ2 GND 1 2 3 4 5 6 7 8 9 10 11 12 24 VCC 23 A8 22 A9 21 WE 20 OE 19 A10 18 CE 17 DQ7 16 DQ6 15 DQ5 14 DQ4 13 DQ3 24-Pin ENCAPSULATED PACKAGE 720-mil EXTENDED PIN DESCRIPTION A0-A10 DQ0-DQ7 - Address Inputs - Data In/Data Out CE - Chip Enable WE - Write Enable OE VCC GND - Output Enable - Power (+5V) - Ground DESCRIPTION The DS1220AB and DS1220AD 16k Nonvolatile SRAMs are 16,384-bit, fully static, nonvolatile SRAMs organized as 2048 words by 8 bits. Each NV SRAM has a self-contained lithium energy source and control circuitry which constantly monitors VCC for an out-of-tolerance condition. When such a condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent data corruption. The NV SRAMs can be used in pl...