Counterfeit and defect prevention
Visual and packaging inspection
Electrical performance verification
Service Email:
[email protected]
>
AT29C040A-90TU
Microchip Technology
IC FLASH 4MBIT PARALLEL 32TSOP
17765 Pcs New Original In Stock
FLASH Memory IC 4Mbit Parallel 90 ns 32-TSOP
Request Quote
(Ships tomorrow)
*Quantity
Minimum 1
Minimum 1
5.0 / 5.0
- (121 Ratings)
AT29C040A-90TU
Product Overview
1241823
DiGi Electronics Part Number
AT29C040A-90TU-DGManufacturer
Microchip Technology
AT29C040A-90TU
Description
IC FLASH 4MBIT PARALLEL 32TSOPInventory
17765 Pcs New Original In Stock
FLASH Memory IC 4Mbit Parallel 90 ns 32-TSOP
Quantity
Minimum 1
Minimum 1
Purchase and inquiry
Warranty & Returns
How to Order
Shipping & Delivery
Quality Assurance
365 - Day Quality Guarantee - Every part fully backed.
90 - Day Refund or Exchange - Defective parts? No hassle.
Limited Stock, Order Now - Get reliable parts without worry.
Global Shipping & Secure Packaging
Worldwide Delivery in 3-5 Business Days
100% ESD Anti-Static Packaging
Real-Time Tracking for Every Order
Secure & Flexible Payment
Credit Card, VISA, MasterCard, PayPal, Western Union, Telegraphic Transfer(T/T) and more
All payments encrypted for security
AT29C040A-90TU Technical Specifications
Category
Memory, Memory
Packaging
-
Series
-
Product Status
Obsolete
DiGi-Electronics Programmable
Not Verified
Memory Type
Non-Volatile
Memory Format
FLASH
Technology
FLASH
Memory Size
4Mbit
Memory Organization
512K x 8
Memory Interface
Parallel
Write Cycle Time - Word, Page
10ms
Access Time
90 ns
Voltage - Supply
4.5V ~ 5.5V
Operating Temperature
-40°C ~ 85°C (TC)
Mounting Type
Surface Mount
Package / Case
32-TFSOP (0.724", 18.40mm Width)
Supplier Device Package
32-TSOP
Base Product Number
AT29C040
Datasheet & Documents
HTML Datasheet
AT29C040A-90TU-DG
Environmental & Export Classification
RoHS Status
ROHS3 Compliant
Moisture Sensitivity Level (MSL)
3 (168 Hours)
REACH Status
REACH Unaffected
ECCN
EAR99
HTSUS
8542.32.0071
Additional Information
Standard Package
156
Reviews
5.0/5.0-(Show up to 5 Ratings)
de desembre 02, 2025
항상 가격이 알맞고 친환경 포장이 마음에 들어요. 앞으로도 계속 이용할게요.
de desembre 02, 2025
保証やアフターサービスが充実しており、長期にわたって安心です。
de desembre 02, 2025
The quality control at Di Digi Electronics is evident in every detail. I trust their products to be of the highest standard for my creative projects.
de desembre 02, 2025
Having access to a diverse array of products enhances customer experience significantly.
de desembre 02, 2025
The team was proactive in resolving any issues, demonstrating their commitment to customer satisfaction.
de desembre 02, 2025
Delivery is consistently fast, and their support helps me get the most out of their products.
de desembre 02, 2025
They demonstrate real leadership in sustainable packaging at an accessible price point.
Publish Evalution
Evalution Message
Please enter your review message.
Please post honest comments and do not post ilegal comments.
Frequently Asked Questions (FAQ)
Can the AT29C040A-90TU be used as a drop-in replacement for the SST39SF040 in a legacy industrial control design, and what are the key differences to validate?
The AT29C040A-90TU is not a guaranteed drop-in replacement for the SST39SF040 despite similar 4Mbit parallel organization. Key differences include write cycle timing (AT29C040A-90TU requires up to 10ms per byte/word versus SST39SF040’s faster 14µs with ESBG), sector protection schemes, and command set compatibility. Designers must verify JEDEC-standard command sequences—Microchip uses software data protection (SDP), while SST uses a proprietary unlock sequence. Signal timing, especially WE# and CE# setup/hold times, must be revalidated in-circuit. Use an oscilloscope to confirm write pulses and ensure firmware handles page program timeouts correctly to avoid corruption in long-term operation.
What are the risks of using the AT29C040A-90TU in a new design given its obsolete status, and how can supply chain reliability be maintained?
Using the AT29C040A-90TU in new designs carries high risk due to its obsolete status—Microchip no longer manufactures it, increasing vulnerability to component shortages and counterfeit parts. For long-term reliability, secure lifetime buys from franchised distributors or pre-screened inventory like the 17,751 pcs available. Mitigate risk by designing with socket adaptability or PCB footprints compatible with modern pin-compatible SPI NOR flashes (e.g., Winbond W25Q32JV) behind a bridge, or use FPGA-based glue logic to emulate parallel timing. Always incorporate burn-in testing and lot traceability for mission-critical applications.
How does the 90 ns access time of the AT29C040A-90TU impact system performance in an 8-bit microcontroller bus interface running at 12 MHz?
The 90 ns access time of the AT29C040A-90TU is marginally compatible with a 12 MHz microcontroller bus (83.3 ns per cycle), leaving minimal timing margin for address decoding and setup delays. This increases risk of read errors without wait-state insertion via hardware READY signal or software delays. To maintain reliability, add one or more wait states in the memory controller configuration and verify timing with 100 MHz+ oscilloscope on actual loaded PCB. Account for temperature and voltage variations—access time may degrade near 4.5V or -40°C. Use controlled impedance traces and minimize stub length on OE# and address lines to prevent ringing.
What PCB layout best practices should be followed when integrating the AT29C040A-90TU in a high-noise industrial environment to prevent unintended writes?
To prevent spurious writes in noisy environments with the AT29C040A-90TU, implement strict PCB layout controls: route address and data lines as short as possible with ground guard traces, suppress WE#, CE#, and OE# signals with 100 Ω series resistors near the device, and use a solid ground plane. Place a 10 µF tantalum capacitor and 100 nF ceramic capacitor within 1 cm of VCC pins to handle transient current during programming. Ensure power-up sequencing meets the 4.5V–5.5V requirement before address stability, and pull unused A/D pins to valid logic levels. If noise persists, consider external Schmitt-trigger buffers on control lines.
Is the AT29C040A-90TU suitable for frequent firmware update applications, and what wear-leveling strategies are needed given its 10ms write cycle limit?
The AT29C040A-90TU is not ideal for frequent firmware updates due to its 10ms write cycle time and limited endurance—typically 100,000 erase/write cycles per sector. Rapid updates can cause premature wear, especially in fixed boot sectors. To extend life, implement software wear leveling: rotate configuration data across multiple sectors and minimize full-chip erases. Avoid byte-level programming in loops; use page programming efficiently. Monitor cumulative write counts in firmware and include margin for end-of-life timing drift. For high-update scenarios, consider migrating to modern SPI NOR with built-in wear leveling or managed flash modules.
Quality Assurance (QC)
DiGi ensures the quality and authenticity of every electronic component through professional inspections and batch sampling, guaranteeing reliable sourcing, stable performance, and compliance with technical specifications, helping customers reduce supply chain risks and confidently use components in production.
AT29C040A-90TU CAD Models
Microchip Technology AT29C040A-90TU PCB symbols & footprints
productDetail
