DS1225AD:64k Nonvolatile SRAM

The DS1225AB and DS1225AD are 65,536-bit, fully static, nonvolatile (NV) SRAMs organized as 8192 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 place of existing 8k x 8 SRAMs directly conforming to the popular bytewide 28-pin DIP standard. The devices also match the pinout of the 2764 EPROM and the 2864 EEPROM, allowing direct substitution while enhancing performance. There is no limit on the number of write cycles that can be executed and no additional support circuitry is required for microprocessor interfacing.

Key Features
  • 10 years minimum data retention in the absence of external power
  • Data is automatically protected during power loss
  • Directly replaces 8k x 8 volatile static RAM or EEPROM
  • Unlimited write cycles
  • Low-power CMOS
  • JEDEC standard 28-pin DIP package
  • Read and write access times of 70ns
  • Lithium energy source is electrically disconnected to retain freshness until power is applied for the first time
  • Full ±10% VCC operating range (DS1225AD)
  • Optional ±5% VCC operating range (DS1225AB)
  • Optional industrial temperature range of -40°C to +85°C, designated IND
DS1225AB, DS1225AD: Pin Assignment
DS1225AB, DS1225AD: Pin Assignment
DataSheet
titleDownload file
DS1225AB-DS1225AD Data SheetDS1225AB-DS1225AD.pdf
Parametrics
Part NumberMemory TypeMemory SizeBus TypeVSUPPLY
(V)
VSUPPLY
(V)
Package/PinsBudgetary
Price
minmaxSee Notes
DS1225ABNV SRAM8K x 8Parallel4.755.25EDIP/28$10.56 @1k
DS1225AD4.55.5EDIP/28
Ordering Information
Part NumberNotesStatusRecommended ReplacementPackageTempRoHS
DS1225AD-15010% Tolerance, 150nsNo Longer AvailableDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CSee data sheet
DS1225AD-150+ActiveEDIP,;28 pin;629.9 mm²0°C to +70°CLead Free
DS1225AD-150IND10% Tolerance, 150nsNo Longer AvailableDS1225AD-70IND+EDIP,;28 pin;629.9 mm²-40°C to +85°CSee data sheet
DS1225AD-17010% Tolerance, 170nsNo Longer AvailableDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CSee data sheet
DS1225AD-170+ActiveDS1225AD-150+EDIP,;28 pin;629.9 mm²0°C to +70°CLead Free
DS1225AD-20010% Tolerance, 200nsNo Longer AvailableDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CSee data sheet
DS1225AD-200+ActiveEDIP,;28 pin;629.9 mm²0°C to +70°CLead Free
DS1225AD-200IND10% Tolerance, 200nsNo Longer AvailableDS1225AD-70IND+EDIP,;28 pin;629.9 mm²-40°C to +85°CSee data sheet
DS1225AD-200IND+ActiveEDIP,;28 pin;629.9 mm²-40°C to +85°CLead Free
DS1225AD-7010% Tolerance, 70nsNo Longer AvailableDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CSee data sheet
Part NumberNotesStatusRecommended ReplacementPackageTempRoHS
DS1225AD-70+ActiveEDIP,;28 pin;629.9 mm²0°C to +70°CLead Free
DS1225AD-70IND10% Tolerance, 70nsNo Longer AvailableDS1225AD-70IND+EDIP,;28 pin;629.9 mm²-40°C to +85°CSee data sheet
DS1225AD-70IND+ActiveEDIP,;28 pin;629.9 mm²-40°C to +85°CLead Free
DS1225AD-8510% Tolerance, 85nsNo Longer AvailableDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CSee data sheet
DS1225AD-85+ActiveDS1225AD-70+EDIP,;28 pin;629.9 mm²0°C to +70°CLead Free
DS1225AB-DS1225AD.pdf DS1225AD
Low-Temperature Data Retention in Nonvolatile SRAM DS1270Y
NV SRAM Device Programmers DS1250Y
Timing Considerations When Using NVSRAM DS1350Y
Tech. Brief 39: NV SRAM Cross Reference Table DS1270Y
NV SRAM Frequently Asked Questions DS1350Y
DS1225AB-DS1225AD.pdf DS1225AD