DS1230Y 256k Nonvolatile SRAM (NV SRAM) DIP-28 (DS1230Y IC)
The DS1230Y is a fully static, 262,144-bit nonvolatile SRAM organized as 32,768 words by 8 bits. Housed in a standard 28-pin DIP package, it is designed to provide high-speed data access with the permanence of nonvolatile memory. The device integrates a self-contained lithium energy source and control circuitry that constantly monitors the supply voltage ($V_{CC}$) for out-of-tolerance conditions. Upon detecting power failure, the IC automatically switches to the internal battery and unconditionally write-protects the memory to prevent data corruption. Unlike EEPROM or Flash, the DS1230Y offers unlimited write cycles and matches the pinout of standard 32k x 8 static RAMs and 28256 EEPROMs, allowing for a direct, high-performance substitution.
This IC is primarily used for configuration storage, calibration constants, and critical usage logs in industrial controllers, medical instrumentation, and telecommunications equipment. It is a highly valued component for electronics projects in India for building DIY vintage computer upgrades, robust data acquisition systems, and embedded controllers that require fast, reliable data retention for over 10 years without external power.
Key Features
- 10 years minimum data retention in the absence of external power
- Unlimited write cycles (no wear-out mechanism like Flash/EEPROM)
- Integrated lithium energy source and self-contained control circuitry
- Automatic write protection during power loss
- Replaces standard 32k x 8 volatile SRAM, EEPROM, or Flash
- Full $\pm$10% $V_{CC}$ operating range
- Low-power CMOS design
- Freshness seal: Battery is disconnected until first power-up to ensure maximum life
- Read and write access times available as fast as 70ns
- JEDEC standard 28-pin DIP footprint
Specifications
- IC Type = Nonvolatile Static RAM (NV SRAM)
- Density = 256Kbit
- Organization = 32,768 words x 8 bits
- Supply Voltage ($V_{CC}$) = 4.5V to 5.5V
- Write Protection Voltage ($V_{TP}$) = 4.25V to 4.5V
- Access Time = 70ns / 85ns / 100ns / 120ns / 150ns / 200ns (Variant dependent)
- Operating Current ($I_{CCO1}$) = 85mA (Max)
- Standby Current ($I_{CCS2}$) = 5mA (Max)
- Package Type = EDIP-28 (Encapsulated DIP)
- Number of Pins = 28
- Mounting Type = Through-Hole
- Operating Temperature = 0 to 70°C (Standard) / -40 to +85°C (IND variant)
Interfaces
- PIN 1 (A14) = Address Input 14
- PIN 2 (A12) = Address Input 12
- PIN 3 (A7) = Address Input 7
- PIN 4 (A6) = Address Input 6
- PIN 5 (A5) = Address Input 5
- PIN 6 (A4) = Address Input 4
- PIN 7 (A3) = Address Input 3
- PIN 8 (A2) = Address Input 2
- PIN 9 (A1) = Address Input 1
- PIN 10 (A0) = Address Input 0
- PIN 11 to 13 (DQ0 to DQ2) = Data Input/Output 0 to 2
- PIN 14 (GND) = Ground (0V)
- PIN 15 to 19 (DQ3 to DQ7) = Data Input/Output 3 to 7
- PIN 20 (CE) = Chip Enable (Active Low)
- PIN 21 (A10) = Address Input 10
- PIN 22 (OE) = Output Enable (Active Low)
- PIN 23 (A11) = Address Input 11
- PIN 24 (A9) = Address Input 9
- PIN 25 (A8) = Address Input 8
- PIN 26 (A13) = Address Input 13
- PIN 27 (WE) = Write Enable (Active Low)
- PIN 28 (VCC) = Positive Supply (+5V)
