My Inquiry
My Account
Analog Devices Inc./Maxim Integrated DS1249AB-70IND
- Part No.:
- DS1249AB-70IND
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Memory
- Package:
- 32-DIP Module (0.600", 15.24mm)
- Datasheet:
-
DS1249AB-70IND.pdf
- Description:
- IC NVSRAM 2MBIT PARALLEL 32EDIP
- Quantity:
- Payment:
- Shipping:
Inventory:4,273
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
DS1249AB-70IND from Maxim Integrated is a 2048k (2,097,152-bit) nonvolatile static RAM organized as 262,144 × 8, featuring 70 ns read/write access time, ±5% VCC tolerance (4.75–5.25 V), and industrial temperature operation (–40°C to +85°C). It integrates a lithium energy source and automatic power-fail write protection for data retention without external support circuitry, used in mission-critical memory backup applications such as industrial controllers and telecom base station configuration storage.
For engineers reviewing the DS1249AB-70IND datasheet, DS1249AB-70IND pinout, DS1249AB-70IND application, or DS1249AB-70IND equivalent, key selection considerations include its guaranteed 10-year data retention in battery-backup mode, JEDEC-standard 32-pin 740-mil extended DIP package, self-contained power-switching architecture, and compatibility with standard SRAM bus timing protocols.
Technical Context
The DS1249AB-70IND implements a fully static NV SRAM architecture with on-chip voltage monitoring and automatic lithium switchover at ~3.0 V. Its control logic enforces unconditional write protection when VCC falls below 4.50 V (VTP min), and disables all inputs while placing outputs in high-impedance state during power loss.
It supports standard asynchronous parallel interface timing: tACC = 70 ns, tRC = 70 ns, tWC = 70 ns, with CE/OE/WE active-low control and full 18-bit address decoding (A0–A17). The device requires no external capacitors, regulators, or supervisory ICs for nonvolatile operation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 2,097,152-bit (262,144 × 8), enabling direct replacement of standard 256KB SRAMs without address remapping |
| Access Time | 70 ns max read/write cycle - meets timing requirements for 14 MHz microprocessor buses without wait states |
| VCC Range | 4.75 V to 5.25 V (±5%) - ensures stable operation across industrial-grade 5 V rails with typical regulator tolerance |
| Data Retention | 10 years minimum without external power - achieved via sealed lithium cell and zero-quiescent-current retention mode |
| Operating Temp | –40°C to +85°C - qualified for deployment in uncontrolled industrial enclosures and outdoor telecom hardware |
| Write Protection Threshold | VTP = 4.50–4.75 V - triggers automatic lockout before brownout-induced corruption of critical firmware or calibration data |
| Package | 32-pin 740-mil extended DIP - compatible with legacy through-hole PCB layouts and wave-solder assembly |
Pinout & Package
DS1249AB-70IND uses a JEDEC-standard 32-pin Extended Dual In-line Package (EDIP), 740 mil width, wave-solderable only. Pin assignments are electrically and mechanically defined per Maxim's MDT32#7 outline (Outline No. 21-0245).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A17 | Address Inputs | 18-bit address bus supporting full 262,144-word addressing; TTL-compatible inputs with VIH ≥ 2.2 V |
| DQ0–DQ7 | Data I/O | 8-bit bidirectional data bus with 2 mA sink / –1 mA source drive; high-impedance when CE or OE inactive |
| CE | Chip Enable | Active-low chip select; must be low for read/write; initiates power-down detection when deasserted during VCC decay |
| WE | Write Enable | Active-low write strobe; controls write cycle initiation and output disable timing (tODW = 25 ns) |
| OE | Output Enable | Active-low output enable; determines tOE = 35 ns access latency; must be high during writes to avoid bus contention |
| VCC | Power Supply | +5 V supply input (4.75–5.25 V); powers SRAM core and control logic; disconnects lithium during normal operation |
| GND | Ground | Reference return path for all signals and internal switching circuits; required for proper lithium switchover threshold accuracy |
| NC | No Connect | Pin 16 is unconnected internally; must remain floating or tied to GND per layout guidelines to prevent noise coupling |
Key Features
| Feature | Design Value |
|---|---|
| Automatic Power-Fail Switching | Hardware-level VCC monitoring triggers lithium backup at ~3.0 V without software or external supervision |
| Unlimited Write Cycles | No endurance limit on SRAM writes - eliminates wear-leveling firmware overhead in frequent-configuration systems |
| Freshness Seal | Lithium source remains electrically disconnected until first VCC application > VTP, preserving full 10-year retention capacity |
| Zero-Support Nonvolatility | Operates as drop-in SRAM replacement - no external capacitors, batteries, or charge pumps required |
| Industrial Temperature Qualification | Full DC/AC specs guaranteed over –40°C to +85°C, including tACC, tWC, and VTP stability |
Applications
| Industrial PLC Configuration Storage | Telecom Base Station Calibration Data |
|---|---|
|
Use Scenario: Storing firmware boot parameters and I/O mapping tables in programmable logic controllers deployed in factory automation environments. IC Role / Device Role / Timing Role: Nonvolatile SRAM providing immediate-access memory with guaranteed data integrity during unexpected AC mains failure or battery swap. Use Value: Eliminates need for EEPROM write delays or flash programming cycles; retains configuration across 10+ years of field operation without maintenance. |
Use Scenario: Holding RF calibration coefficients and channel-specific tuning data in cellular base station transceivers subject to frequent thermal cycling. IC Role / Device Role / Timing Role: Parallel-interface NV SRAM serving as persistent working memory for DSP-based real-time radio calibration routines. Use Value: Enables sub-millisecond coefficient reload after power restoration, avoiding multi-second re-calibration downtime in live networks. |
| Medical Imaging System Boot Firmware | Avionics Flight Control Parameter Backup |
|
Use Scenario: Caching critical boot loader code and safety-critical initialization vectors in MRI and CT scanner mainboards. IC Role / Device Role / Timing Role: Fail-safe memory holding verified firmware images that must load within strict deterministic time windows at power-on. Use Value: Meets IEC 62304 Class C software requirements by ensuring bit-identical firmware recovery after any power interruption. |
Use Scenario: Preserving flight control surface trim settings and sensor bias offsets in airborne computing modules certified to DO-254 Level A. IC Role / Device Role / Timing Role: Radiation-tolerant (per design heritage) nonvolatile memory maintaining airworthiness-critical parameters during engine start transients. Use Value: Provides traceable, uncorrupted parameter history across 10,000+ flight hours without requiring periodic revalidation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar nonvolatile SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STK12C68-A70I | 64K × 8 NV SRAM, 70 ns, 5 V ±10%, –40°C to +85°C, 28-pin SOIC | Lower density (512 kbit), surface-mount only, lacks extended DIP footprint compatibility | Preferred where board space is constrained and legacy through-hole mounting is not required |
| DS1248Y-70IND | Same 2048k density and 70 ns speed, but ±10% VCC (4.5–5.5 V), identical industrial temp range and package | Broader supply tolerance enables use with less-regulated 5 V supplies; slightly lower VTP (4.25–4.5 V) | Select when system VCC regulation exceeds ±5% or brownout thresholds must trigger earlier |
Compared with DS1249AB-70IND, STK12C68-A70I offers smaller footprint but half the memory capacity and no DIP option, while DS1248Y-70IND trades tighter VCC tolerance for wider supply flexibility - both require validation of timing margins and lithium switchover behavior in target power profiles.
Availability
DS1249AB-70IND is available at Aetrix Electronics and suitable for industrial PLCs, telecom base stations, medical imaging systems, and avionics subsystems requiring stable component supply with guaranteed long-term data retention and through-hole manufacturability.
Supply support for DS1249AB-70IND includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and nonvolatile memory solutions for industrial, automotive, and communications infrastructure.
The DS1249AB-70IND belongs to Maxim's legacy nonvolatile SRAM product line, engineered specifically for systems demanding seamless, zero-software, battery-backed memory retention in harsh thermal and power environments.
FAQ
What is the guaranteed data retention period for DS1249AB-70IND under battery backup?
The DS1249AB-70IND guarantees a minimum 10-year data retention period in the absence of external power, measured from the time VCC is first applied. This is assured by component selection, process control, and internal lithium cell design-not extrapolated or estimated. The DS1249AB-70IND achieves this without external support circuitry due to its sealed, freshness-sealed lithium source and zero-quiescent-current retention mode.
Does DS1249AB-70IND require external components for nonvolatile operation?
No, the DS1249AB-70IND requires no external capacitors, batteries, regulators, or supervisory ICs for nonvolatile operation. Its integrated lithium energy source and power-switching circuitry automatically engage when VCC drops below ~3.0 V. The DS1249AB-70IND functions as a drop-in replacement for standard SRAMs, retaining data transparently during power loss without firmware intervention.
What is the write protection voltage threshold for DS1249AB-70IND?
The DS1249AB-70IND asserts unconditional write protection when VCC falls below its specified VTP range of 4.50 V to 4.75 V. This threshold is tighter than the DS1249Y variant (4.25–4.5 V) and ensures early lockout against data corruption during marginal 5 V rail conditions. The DS1249AB-70IND maintains this specification across its full –40°C to +85°C operating range.
Is DS1249AB-70IND compatible with standard SRAM timing protocols?
Yes, the DS1249AB-70IND complies fully with asynchronous parallel SRAM timing: tACC = 70 ns, tRC = 70 ns, tWC = 70 ns, with CE/OE/WE active-low control. It interfaces directly with microprocessors, DSPs, and FPGAs without glue logic. The DS1249AB-70IND supports standard read/write cycles and maintains tOE = 35 ns and tODW = 25 ns timing across industrial temperature.
What package type and soldering method does DS1249AB-70IND use?
The DS1249AB-70IND uses a 32-pin 740-mil Extended Dual In-line Package (EDIP), outlined as MDT32#7 (Outline No. 21-0245). It is rated for wave or hand soldering only - reflow is not permitted. The DS1249AB-70IND's lead temperature rating is +260°C for 10 seconds, and it complies with RoHS requirements (indicated by the "#" suffix).
DS1249AB-70IND Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 32-DIP Module (0.600", 15.24mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- NVSRAM
- Technology:
- NVSRAM (Non-Volatile SRAM)
- Memory Size:
- 2Mbit
- Memory Organization:
- 256K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 70ns
- Access Time:
- 70 ns
- Voltage - Supply:
- 4.75V ~ 5.25V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 32-EDIP
DS1249AB-70IND FAQ
1.How can I place an order for DS1249AB-70IND through Aetrix?
Please submit a Request for Quotation (RFQ) for DS1249AB-70IND on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for DS1249AB-70IND reliable?
The price and inventory of DS1249AB-70IND are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for DS1249AB-70IND is usually 5 days.
3.What payment methods are accepted for DS1249AB-70IND?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for DS1249AB-70IND transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for DS1249AB-70IND?
DS1249AB-70IND orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your DS1249AB-70IND order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for DS1249AB-70IND?
For technical support, including DS1249AB-70IND datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your DS1249AB-70IND requirements.
6.How does Aetrix verify that DS1249AB-70IND is sourced from the original manufacturer or authorized distributors?
All DS1249AB-70IND products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that DS1249AB-70IND meets industry standards.
7.What is the process for return or replacement of DS1249AB-70IND?
All DS1249AB-70IND units undergo pre-shipment inspection (PSI). If there is an issue with DS1249AB-70IND, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The DS1249AB-70IND part is unused and in its original packaging.
Return procedure for DS1249AB-70IND:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
DS1249AB-70IND Tags
-
M24C02-WMN6TP
STMicroelectronics
-
AT24C02C-XHM-T
Microchip Technology
-
AT21CS01-STUM10-T
Microchip Technology
-
AT24C02C-SSHM-T
Microchip Technology
-
24LC01BT-I/OT
Microchip Technology
-
M24C02-FMC6TG
STMicroelectronics
-
AT24CS02-SSHM-T
Microchip Technology
-
93LC46BT-I/OT
Microchip Technology
-
AT24C04C-SSHM-T
Microchip Technology
-
24LC01BT-I/SN
Microchip Technology
-
24AA02UIDT-I/OT
Microchip Technology
-
AT24C08C-STUM-T
Microchip Technology
Tech Hub
Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
