My Inquiry
My Account
Texas Instruments BQ4015LYMA-70N
- Part No.:
- BQ4015LYMA-70N
- Manufacturer:
- Texas Instruments
- Category:
- Memory
- Package:
- 32-DIP Module (0.610", 15.49mm)
- Datasheet:
-
BQ4015LYMA-70N.pdf
- Description:
- IC NVSRAM 4MBIT PAR 32DIP MODULE
- Quantity:
- Payment:
- Shipping:
Inventory:2,424
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BQ4015LYMA-70N from Texas Instruments is a 512 k × 8 nonvolatile static RAM (NVSRAM) with integrated lithium backup, 3.3-V operation, 70-ns access time, and 32-pin DIP module packaging. It functions as a standard SRAM during valid power and automatically switches to battery-backed retention during power loss-used in industrial control data logging where persistent memory without write endurance limits is required.
For engineers reviewing the BQ4015LYMA-70N datasheet, BQ4015LYMA-70N pinout, BQ4015LYMA-70N application, or BQ4015LYMA-70N equivalent, key selection considerations include its 3.3-V VPFD threshold (2.90 V typical), 10-year data retention, automatic write-protection timing (tCER = 85 ms max), and compatibility with industry-standard 4-Mb SRAM address/data bus layouts.
Technical Context
The BQ4015LYMA-70N integrates a CMOS SRAM core, power-fail detection circuitry, and a sealed lithium coin cell within a single 32-pin DIP module. Its VPFD threshold is fixed at 2.90 V (typ) for 3.3-V systems, triggering write-protection and backup switchover before VCC drops below VSO (2.9 V).
During power-up, it enforces a 85-ms chip-enable recovery window (tCER) before allowing writes; during power-down, it guarantees write-protection activation within 100 μs (tWPT max) after VCC crosses VPFD. All I/O pins enter high-impedance state upon protection activation, and internal battery isolation ensures ≤0.5% annual self-discharge prior to first power application.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 524,288 × 8 bits (4,194,304 total bits); supports full byte-wide parallel interface without banking or interleaving. |
| Supply Voltage | 3.0 V to 3.6 V nominal; designed exclusively for 3.3-V systems with ±10% tolerance (VCC = 3.3 V ±10%). |
| Access Time | 70 ns maximum; enables direct interfacing with microcontrollers and FPGAs operating at ≤14 MHz bus clocks. |
| Power-Fail Threshold | 2.85 V (min) to 2.95 V (max), 2.90 V typical; triggers automatic write-protection before data corruption risk in 3.3-V rails. |
| Data Retention | ≥10 years without external power; achieved via low-leakage CMOS SRAM and isolated lithium cell with <0.5%/year self-discharge pre-activation. |
| Standby Current | 0.1 μA (ISB1) when CE = VIH; ensures minimal battery drain during long-term retention mode. |
| Write-Protection Delay | 40–150 μs (tWPT); provides deterministic window for ongoing memory cycles to complete before protection engages. |
Pinout & Package
32-pin dual in-line package (DIP) module, MA package type, through-hole mounting. Pin layout matches industry-standard 4-Mb SRAM footprint for drop-in replacement in legacy designs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address inputs | 19-bit address bus supporting full 524,288-word addressing; compatible with standard 4-Mb SRAM address mapping. |
| DQ0–DQ7 | Data input/output | 8-bit bidirectional data bus; high-impedance on power-fail or when OE/CE inactive to prevent bus contention. |
| CE | Chip-enable input | Active-low enable controlling device selection; initiates tCER delay on power-up before write operations resume. |
| OE | Output-enable input | Active-low control for output drivers; allows read-only access while CE remains active and WE is high. |
| WE | Write-enable input | Active-low signal enabling write cycles; must be synchronized with CE and address setup per AC timing table. |
| VCC | Supply voltage input | 3.3-V primary power rail; monitored continuously for VPFD crossing to trigger nonvolatile transition logic. |
| VSS | Ground | System reference ground; shared return path for SRAM core, control logic, and backup supply switching. |
Key Features
| Feature | Design Value |
|---|---|
| Automatic Power-Fail Response | Hardware-level detection and switchover without firmware intervention; eliminates need for external supervisors or backup controllers. |
| Zero External Components Required | Self-contained module with integrated lithium cell, charge isolation, and monitoring circuitry-no capacitors, regulators, or diodes needed. |
| Lithium Cell Isolation | Factory-isolated backup cell with <0.5% annual self-discharge; prevents battery drain until first VCC application, maximizing shelf life. |
| Unlimited Write Cycles | Standard SRAM write endurance-no wear leveling, erase cycles, or write latency penalties unlike EEPROM or Flash. |
| Industry-Standard Pinout | Pin-compatible with JEDEC 4-Mb SRAMs (e.g., AS6C4008, CY62167); enables retrofit into existing 32-pin DIP layouts without PCB changes. |
Applications
| Industrial Data Logger | Medical Device Configuration Store |
|---|---|
Use Scenario: Continuous recording of sensor readings and fault events in programmable logic controllers with intermittent mains power. IC Role / Device Role / Timing Role: Nonvolatile scratchpad memory holding last-known operational state and calibration offsets across unexpected outages. Use Value: Eliminates need for external EEPROM write routines and guarantees atomic state preservation within 150 μs of brownout onset. |
Use Scenario: Storing patient-specific therapy parameters and usage history in portable infusion pumps subject to frequent battery swaps. IC Role / Device Role / Timing Role: Retentive configuration register bank retaining critical settings during power cycling between alkaline and rechargeable modes. Use Value: Ensures FDA-compliant parameter persistence without software-initiated save sequences or risk of partial-write corruption. |
| Telecom Line Card Buffer | Avionics Black Box Recorder |
Use Scenario: Caching protocol stack state and call routing tables in DSLAM line cards experiencing grid instability. IC Role / Device Role / Timing Role: High-speed SRAM buffer with fail-safe retention during AC/DC converter transients or fuse blowouts. Use Value: Maintains service continuity by restoring full session context within 85 ms of power restoration-no retraining or handshake delays. |
Use Scenario: Capturing flight control surface positions and engine telemetry in UAVs with constrained board space and no external backup power. IC Role / Device Role / Timing Role: Primary crash-data memory capturing last 30 seconds of operation using deterministic write-protection timing. Use Value: Guarantees forensic data integrity even during rapid voltage collapse (<300 μs slew), meeting DO-160 Section 22 transient immunity requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar nonvolatile SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CY14B108L-ZSP25XI | 8-Mb density, SPI interface, 25-MHz max clock, no parallel bus; requires firmware driver layer. | Suitable for new designs with microcontroller SPI peripherals but incompatible with legacy parallel-addressed systems. | Select only if migrating from parallel to serial architecture and accepting added software overhead. |
| AS6C4008-70ZIN | Standard 512k×8 SRAM, no battery or power-fail logic; requires external supervisor IC and backup capacitor. | Lower cost for powered applications but adds ≥4 components and design complexity for retention capability. | Choose only when system already includes discrete power-monitoring and backup power circuitry. |
Compared with CY14B108L-ZSP25XI and AS6C4008-70ZIN, the BQ4015LYMA-70N delivers plug-and-play nonvolatility in legacy parallel-bus systems-eliminating both firmware integration effort and external component count while guaranteeing deterministic 10-year retention without runtime management.
Availability
BQ4015LYMA-70N is available at Aetrix Electronics and suitable for industrial data loggers, medical device configuration stores, and telecom line card buffers requiring stable component supply despite its OBSOLETE status per TI's lifecycle notice.
Supply support for BQ4015LYMA-70N 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
Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and communications markets since 1930.
The BQ4015LYMA-70N belongs to TI's legacy NVSRAM product line, engineered specifically for systems needing seamless, hardware-governed nonvolatility in space-constrained, reliability-critical applications without redesigning memory interfaces.
FAQ
What is the guaranteed data retention period for BQ4015LYMA-70N under zero-power conditions?
The BQ4015LYMA-70N guarantees ≥10 years of data retention without external power, measured from first VCC application onward. This is achieved via ultra-low-leakage CMOS SRAM and an isolated lithium cell with ≤0.5% annual self-discharge prior to activation. The 10-year figure is validated at TA = 25°C and reflects accumulated off-time-not calendar life.
Does BQ4015LYMA-70N require external components to achieve nonvolatile operation?
No, the BQ4015LYMA-70N requires zero external components for nonvolatile operation. Its monolithic DIP module integrates the SRAM array, power-fail detection circuitry, lithium backup cell, and switchover logic. Unlike discrete SRAM + supervisor solutions, it needs no capacitors, diodes, regulators, or firmware initialization to deliver automatic write-protection and retention.
What is the exact power-fail detect (VPFD) threshold voltage for BQ4015LYMA-70N?
The BQ4015LYMA-70N has a VPFD threshold of 2.85 V (min), 2.90 V (typ), and 2.95 V (max) - calibrated specifically for 3.3-V systems. This threshold is factory-trimmed and not user-adjustable. It triggers write-protection and lithium switchover before VCC drops to VSO (2.9 V), ensuring data integrity during brownouts.
Is BQ4015LYMA-70N pin-compatible with standard 4-Mb SRAMs?
Yes, the BQ4015LYMA-70N uses a 32-pin DIP (MA package) with identical pinout to industry-standard 4-Mb parallel SRAMs such as the AS6C4008 and CY62167. Address lines A0–A18, data lines DQ0–DQ7, and control signals CE/OE/WE map directly-enabling drop-in replacement in existing PCB layouts without trace modifications.
How does BQ4015LYMA-70N handle write operations during power-up recovery?
After VCC rises above VPFD, the BQ4015LYMA-70N enforces a chip-enable recovery time (tCER) of up to 85 ms during which all write operations are blocked-even if CE and WE are asserted. This prevents premature writes before the host processor and power supply stabilize. Normal SRAM operation resumes only after tCER expires, ensuring deterministic system boot behavior.
BQ4015LYMA-70N Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 32-DIP Module (0.610", 15.49mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- NVSRAM
- Technology:
- NVSRAM (Non-Volatile SRAM)
- Memory Size:
- 4Mbit
- Memory Organization:
- 512K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 70ns
- Access Time:
- 70 ns
- Voltage - Supply:
- 3V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 32-DIP Module (18.42x42.8)
BQ4015LYMA-70N FAQ
1.How can I place an order for BQ4015LYMA-70N through Aetrix?
Please submit a Request for Quotation (RFQ) for BQ4015LYMA-70N 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 BQ4015LYMA-70N reliable?
The price and inventory of BQ4015LYMA-70N are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BQ4015LYMA-70N is usually 5 days.
3.What payment methods are accepted for BQ4015LYMA-70N?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BQ4015LYMA-70N transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BQ4015LYMA-70N?
BQ4015LYMA-70N orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BQ4015LYMA-70N 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 BQ4015LYMA-70N?
For technical support, including BQ4015LYMA-70N datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BQ4015LYMA-70N requirements.
6.How does Aetrix verify that BQ4015LYMA-70N is sourced from the original manufacturer or authorized distributors?
All BQ4015LYMA-70N 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 BQ4015LYMA-70N meets industry standards.
7.What is the process for return or replacement of BQ4015LYMA-70N?
All BQ4015LYMA-70N units undergo pre-shipment inspection (PSI). If there is an issue with BQ4015LYMA-70N, 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 BQ4015LYMA-70N part is unused and in its original packaging.
Return procedure for BQ4015LYMA-70N:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BQ4015LYMA-70N 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
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 …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
