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Microchip Technology AT29BV040A-20TU
- Part No.:
- AT29BV040A-20TU
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-TFSOP (0.724", 18.40mm Width)
- Datasheet:
-
AT29BV040A-20TU.pdf
- Description:
- IC FLASH 4MBIT PARALLEL 32TSOP
- Quantity:
- Payment:
- Shipping:
Inventory:4,606
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Product details
Overview
AT29BV040A-20TU from Microchip Technology (formerly Atmel) is a 4-Mbit (512K × 8) single-supply Flash memory IC designed for in-system reprogrammability in embedded boot code and firmware storage applications. It operates from 2.7V to 3.6V, delivers 200 ns read access time, supports sector-based programming with 2048 × 256-byte sectors, and features dual 16K-byte boot blocks with independent lockout capability.
For engineers reviewing the AT29BV040A-20TU datasheet, AT29BV040A-20TU pinout, AT29BV040A-20TU application, or AT29BV040A-20TU equivalent, this page provides verified technical context, real-world use cases, validated alternatives, and supply-chain support details specific to the TSOP-32 industrial-grade variant.
Technical Context
The AT29BV040A-20TU implements a software-controlled sector erase-and-program architecture with no external high-voltage programming required. It uses a three-byte unlock sequence (AAh/55h/A0h) followed by byte-load timing ≤150 µs per byte, and internally manages erase-before-write cycles without external command intervention.
It supports two distinct protection mechanisms: hardware-level VCC-sense and noise filtering on WE/CE inputs, plus software data protection with full sector locking. Boot block lockout is independently configurable for the first and last 16K-byte regions, disabling both program and chip-erase functions when enabled.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 4 Mbit (524,288 × 8), organized as 2048 sectors of 256 bytes each |
| Read Access Time | 200 ns - enables direct replacement for EPROMs in legacy 8-bit microcontroller boot interfaces |
| Supply Voltage | 2.7V–3.6V - single-supply operation compatible with 3.3V logic systems without level shifting |
| Active Current | 15 mA at 5 MHz - low power consumption suitable for battery-backed or energy-constrained systems |
| Standby Current | 50 µA CMOS standby - enables ultra-low-power retention during system sleep modes |
| Endurance | 10,000 program/erase cycles per sector - sufficient for field firmware updates over product lifetime |
| Operating Temp | −40°C to +85°C - qualified for industrial environments including automotive body control modules |
Pinout & Package
AT29BV040A-20TU is packaged in a 32-lead Thin Small Outline Package (TSOP Type I, 8 × 20 mm, JEDEC MO-142 BD), pin-compatible with industry-standard 32-pin Flash memory sockets.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus supporting full 512K-word addressing; A0–A7 select byte within sector, A8–A18 select sector |
| CE | Chip Enable | Active-low chip select; must be stable before address setup to avoid bus contention during read/write |
| OE | Output Enable | Active-low output control; used with CE to gate data output during read; high during programming to disable outputs |
| WE | Write Enable | Active-low write strobe; controls latching of address/data during byte load; must be high during read mode |
| I/O0–I/O7 | Bidirectional Data Bus | 8-bit multiplexed data path; latches input during WE/CE pulse falling edge; drives valid data on read after tACC |
| NC | No Connect | Pin 16 (PLCC) / Pin 16 (TSOP) - unconnected; must remain floating per datasheet |
| VCC | Power Supply | 2.7V–3.6V primary supply; internal voltage sensing prevents programming below 1.8V typical |
| GND | Ground Reference | Signal and power ground reference; decoupling capacitor (0.1 µF) required within 10 mm of VCC/GND pins |
Key Features
| Feature | Design Value |
|---|---|
| Single 2.7V–3.6V Supply | Eliminates need for separate 5V or 12V programming rails - simplifies power design and reduces BOM count |
| 20 ms Max Sector Program Cycle | Enables rapid field firmware patching; full 256-byte sector written in guaranteed ≤20 ms without external timing control |
| DATA Polling (I/O7) | Allows host MCU to detect program completion via read-back without fixed delay loops or external interrupt signals |
| Toggle Bit (I/O6) | Provides asynchronous, non-intrusive status monitoring during program/erase - usable with any static address |
| Boot Block Lockout | Prevents accidental overwrite of critical startup code in first/last 16K-byte regions - essential for fail-safe bootloader integrity |
Applications
| Industrial PLC Firmware Storage | Medical Device Boot Code Retention |
|---|---|
|
Use Scenario: Storing firmware images and configuration parameters in programmable logic controllers deployed in factory automation environments with wide temperature swings and EMI exposure. IC Role / Device Role / Timing Role: Nonvolatile boot memory holding initialization routines and safety-critical control algorithms executed at power-on reset. Use Value: 10,000-cycle endurance and −40°C to +85°C rating ensure reliable operation across 10+ years of scheduled firmware updates without field replacement. |
Use Scenario: Holding certified bootloader and diagnostic firmware in Class II medical instruments requiring traceable, tamper-resistant code storage. IC Role / Device Role / Timing Role: Secure boot memory with independent lockout for first 16K bytes - prevents unauthorized modification of FDA-approved startup sequences. Use Value: Dual boot block lockout and software/hardware protection layers meet IEC 62304 SW safety requirements for Level C software. |
| Automotive Body Control Module | Legacy Industrial HMI Display |
|
Use Scenario: Storing calibration data and feature-enable bits in door module ECUs where infrequent but mission-critical updates occur over CAN diagnostics. IC Role / Device Role / Timing Role: In-system reprogrammable Flash memory interfaced directly to 8-bit microcontroller address/data bus with no external glue logic. Use Value: 200 ns read access matches timing budgets of 8051/HC11 derivatives; 50 µA standby current extends battery life during vehicle sleep mode. |
Use Scenario: Replacing obsolete 27C040 EPROMs in aging human-machine interface panels used in CNC machine tools and HVAC controllers. IC Role / Device Role / Timing Role: Drop-in EPROM replacement with identical pinout and read protocol - requires only minor PCB layout revision for VCC routing. Use Value: Software data protection eliminates need for UV-erasable windowed packages; green Pb/Halide-free packaging meets RoHS compliance mandates. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Flash memory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SST39VF400A-70-4C-NHE | 4 Mbit, 70 ns access, 3.0V–3.6V supply, 44-pin TSOP; lacks boot block lockout and DATA polling | Higher speed but no dedicated boot protection; requires external polling logic or fixed delays | Preferred when faster read performance is prioritized over secure boot features |
| MX29LV400CBTI-70G | 4 Mbit, 70 ns access, 2.7V–3.6V supply, 48-pin TSOP; includes CFI query and uniform 64K-block erase | Supports standard CFI interface for auto-detection but uses larger erase granularity (64K vs 256B sectors) | Recommended for new designs requiring standardized flash drivers and broader ecosystem tool support |
Compared with AT29BV040A-20TU, SST39VF400A offers faster reads but sacrifices boot security and self-polling simplicity, while MX29LV400CBTI provides CFI compatibility and larger erase blocks - making AT29BV040A-20TU optimal for cost-sensitive, legacy-compatible, and boot-critical implementations where fine-grained sector control and lockout are mandatory.
Availability
AT29BV040A-20TU is available at Aetrix Electronics and suitable for industrial PLC firmware storage, medical device boot code retention, and automotive body control module applications requiring stable component supply and long-term lifecycle assurance.
Supply support for AT29BV040A-20TU 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
Microchip Technology acquired Atmel in 2016 and maintains full support for legacy Atmel Flash products, including documentation, validation, and long-term supply commitments.
The AT29BV040A belongs to Atmel's 2.7V-only Flash memory family, engineered specifically for in-system reprogrammability in space-constrained, low-power embedded systems requiring robust boot code storage without high-voltage programming infrastructure.
FAQ
What is the maximum operating temperature range for the AT29BV040A-20TU?
The AT29BV040A-20TU is rated for industrial temperature operation from −40°C to +85°C. This specification is confirmed in the "DC and AC Operating Range" section of the official datasheet (document 0383J–FLASH–9/08), and applies to the -20TU variant in TSOP-32 packaging. The device maintains full functionality-including 200 ns read access and 20 ms sector programming-across this entire range.
Does the AT29BV040A-20TU require external high-voltage programming signals?
No, the AT29BV040A-20TU does not require external high-voltage programming signals. It operates exclusively from a single 2.7V–3.6V supply, using an internal charge pump and software-controlled unlock sequence (AAh/55h/A0h) to enable sector programming. This eliminates the need for 12V programming rails or external voltage translators in system design.
How does the boot block lockout feature work on the AT29BV040A-20TU?
The AT29BV040A-20TU includes two independent 16K-byte boot blocks-one at the lowest addresses (0x00000–0x03FFF) and one at the highest (0x7C000–0x7FFFF). Each can be permanently locked via a seven-step software algorithm. Once locked, that block cannot be erased or programmed, and chip-erase is disabled. Lock status is readable via software identification mode at addresses 00002H and 7FFF2H.
Can the AT29BV040A-20TU be used as a direct replacement for standard EPROMs like the 27C040?
Yes, the AT29BV040A-20TU is functionally and pin-compatible with 27C040 EPROMs in read mode: same 32-pin TSOP/PLCC footprint, identical CE/OE/WE control logic, and EPROM-like read timing. However, programming requires software unlock and sector-based writes-not UV erasure-so system firmware must implement the AT29BV040A-20TU's specific byte-load protocol.
What methods are available to detect program completion on the AT29BV040A-20TU?
The AT29BV040A-20TU provides two hardware-supported methods: DATA polling on I/O7 (complement of loaded data until completion, then true data) and Toggle Bit detection on I/O6 (toggles between 0/1 during programming, stabilizes at completion). Both methods allow the host processor to monitor status without fixed delays or external timers, and either may be used at any point during the program cycle.
AT29BV040A-20TU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 32-TFSOP (0.724", 18.40mm Width)
- Packaging:
- Tray
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- FLASH
- Technology:
- FLASH
- Memory Size:
- 4Mbit
- Memory Organization:
- 512K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 20ms
- Access Time:
- 200 ns
- Voltage - Supply:
- 2.7V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-TSOP
AT29BV040A-20TU FAQ
1.How can I place an order for AT29BV040A-20TU through Aetrix?
Please submit a Request for Quotation (RFQ) for AT29BV040A-20TU 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 AT29BV040A-20TU reliable?
The price and inventory of AT29BV040A-20TU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT29BV040A-20TU is usually 5 days.
3.What payment methods are accepted for AT29BV040A-20TU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT29BV040A-20TU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT29BV040A-20TU?
AT29BV040A-20TU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT29BV040A-20TU 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 AT29BV040A-20TU?
For technical support, including AT29BV040A-20TU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT29BV040A-20TU requirements.
6.How does Aetrix verify that AT29BV040A-20TU is sourced from the original manufacturer or authorized distributors?
All AT29BV040A-20TU 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 AT29BV040A-20TU meets industry standards.
7.What is the process for return or replacement of AT29BV040A-20TU?
All AT29BV040A-20TU units undergo pre-shipment inspection (PSI). If there is an issue with AT29BV040A-20TU, 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 AT29BV040A-20TU part is unused and in its original packaging.
Return procedure for AT29BV040A-20TU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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