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Renesas AT45DB321D-MWU
- Part No.:
- AT45DB321D-MWU
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 8-VDFN Exposed Pad
- Datasheet:
-
AT45DB321D-MWU.pdf
- Description:
- IC FLASH 32MBIT SPI 66MHZ 8VDFN
- Quantity:
- Payment:
- Shipping:
Inventory:4,657
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Product details
Overview
AT45DB321D-MWU from Microchip Technology (formerly Atmel) is a 32Mb serial DataFlash memory IC with SPI-compatible RapidS interface, 512/528-byte page size, dual 512/528-byte SRAM buffers, and industrial temperature support. It operates from a single 2.5V–3.6V supply, delivers up to 66MHz read throughput, and enables continuous array reads ideal for code shadowing in embedded microcontroller systems.
For engineers reviewing the AT45DB321D-MWU datasheet, AT45DB321D-MWU pinout, AT45DB321D-MWU application, or AT45DB321D-MWU equivalent, key selection criteria include page-program timing, buffer-to-flash transfer latency, sector lockdown security, RDY/BUSY signaling behavior, and compatibility with legacy SPI Mode 0/3 host controllers.
Technical Context
The AT45DB321D-MWU implements a sequential-access flash architecture with two independent 512/528-byte SRAM buffers enabling concurrent data reception and flash reprogramming. Its RapidS interface supports SPI Modes 0 and 3 at up to 66MHz, with three distinct continuous read opcodes (03H, 0BH, E8H) optimized for low-, high-, and legacy-frequency operation.
Memory organization comprises 8,192 pages across 64 sectors, supporting four erase granularities: page (512 B), block (4 KB), sector (64 KB), and chip (32 Mb). All program/erase operations are self-timed and signaled via the open-drain RDY/BUSY pin, while hardware write protection (WP) and sector lockdown provide physical-layer security independent of software commands.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory density | 32 Mbit (4 MB) organized as 8,192 × 512/528-byte pages |
| Interface speed | Up to 66 MHz SCK for continuous reads (0BH/E8H); 33 MHz max for 03H mode |
| Supply voltage | 2.5V–3.6V single supply - no charge pump or VPP required |
| Power consumption | 7 mA typical active read current; 25 µA standby; 15 µA deep power-down |
| Erase endurance | 100,000 program/erase cycles per page minimum |
| Data retention | 20 years at 85°C |
| Operating temperature | −40°C to +85°C industrial grade |
Pinout & Package
AT45DB321D-MWU is packaged in an 8-pin MLF (VDFN) with exposed thermal pad (floating or GND), compatible with space-constrained PCB layouts and reflow assembly. Pin functions align with standard SPI+control interface requirements.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-low enable; falling edge initiates command sequence; rising edge terminates self-timed operations |
| SCK | Serial Clock | Input clock for SPI; data latched on rising edge (SI), output shifted on falling edge (SO) |
| SI | Serial Input | Command, address, and data input path; MSB-first protocol |
| SO | Serial Output | Data output path; tri-stated when CS is high |
| WP | Write Protect | Hardware lockout: low state disables all protected-sector program/erase regardless of software settings |
| RESET | Reset | Active-low hard reset; terminates ongoing operation and returns state machine to idle |
| RDY/BUSY | Ready/Busy indicator | Open-drain output pulled high externally; driven low during program/erase/buffer transfers |
| VCC / GND | Power supply | Single 2.5–3.6V supply; GND reference for all I/O and internal logic |
Key Features
| Feature | Design Value |
|---|---|
| Dual SRAM buffers | Two independent 512/528-byte buffers enable simultaneous receive-and-reprogram operation without CPU stall |
| Flexible page size | User-selectable 512- or 528-byte pages; factory-configurable default simplifies firmware porting |
| Continuous array read | Zero-overhead wraparound reads across page and array boundaries - eliminates address management overhead in bootloaders |
| Sector lockdown | Hardware-enforced read/write lock per sector using dedicated security register - prevents runtime tampering with firmware partitions |
| JEDEC ID support | Standard manufacturer (0x1F) and device (0x26) ID readout - enables automated flash detection and configuration in production test |
Applications
| Firmware Storage | Secure Bootloader |
|---|---|
Use Scenario: Storing application firmware images for microcontrollers with limited internal flash. IC Role / Device Role / Timing Role: Nonvolatile storage medium accessed via SPI during boot or OTA update; supports rapid sequential reads for code shadowing into RAM. Use Value: 66MHz continuous read eliminates wait states during instruction fetch; dual buffers allow background firmware download while executing prior version. | Use Scenario: Hosting cryptographically signed bootloader code that validates subsequent firmware before execution. IC Role / Device Role / Timing Role: Secure, tamper-resistant storage for immutable bootloader binary and public key certificates. Use Value: Sector lockdown prevents overwrite or corruption of bootloader region; 128-byte security register stores keys and device ID for chain-of-trust verification. |
| Data Logging | Industrial HMI Configuration |
Use Scenario: Recording sensor timestamps and measurements in battery-powered edge nodes. IC Role / Device Role / Timing Role: High-endurance, low-power nonvolatile buffer for cyclic logging; leverages page erase granularity to minimize wear. Use Value: 100,000 erase cycles per page and 15 µA deep power-down extend battery life; RDY/BUSY pin enables precise sleep/wake coordination. | Use Scenario: Persisting UI layout, language packs, and calibration parameters in human-machine interface panels. IC Role / Device Role / Timing Role: Field-upgradable configuration store accessible over SPI from ARM Cortex-A/RISC-V SoC. Use Value: 64KB sector erase allows atomic updates of language assets; JEDEC ID ensures correct firmware-image pairing during field service. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial flash memory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Winbond W25Q32JVSSIQ | 32Mb Quad SPI NOR flash; 4-line I/O; no SRAM buffers; 133MHz QSPI clock; no sector lockdown | Higher throughput for XIP; lacks concurrent buffer operation and hardware sector protection | Choose for execute-in-place (XIP) performance where buffer concurrency and lockdown are not required |
| Macronix MX25L3233FZNI-10G | 32Mb standard SPI NOR flash; 104MHz max clock; no dual buffers; no security register or device ID | Lower cost; simpler command set; no built-in security features or continuous-read optimization | Choose for cost-sensitive designs requiring basic firmware storage without advanced security or streaming features |
Compared with W25Q32JVSSIQ and MX25L3233FZNI-10G, the AT45DB321D-MWU uniquely combines dual SRAM buffers for zero-latency streaming, hardware-enforced sector lockdown, and JEDEC-compliant identification - making it optimal for secure, real-time firmware and data logging where concurrent access and tamper resistance are critical.
Availability
AT45DB321D-MWU is available at Aetrix Electronics and suitable for firmware storage, secure bootloader deployment, industrial data logging, and HMI configuration management requiring stable component supply and long-term lifecycle assurance.
Supply support for AT45DB321D-MWU 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 the DataFlash product family, including documentation, validation, and long-term manufacturing commitment.
The AT45DB321D-MWU belongs to the Atmel DataFlash® series, designed specifically for high-reliability, low-pin-count serial flash applications demanding concurrent buffering, flexible erase granularity, and hardware-level security in industrial and embedded systems.
FAQ
What is the maximum clock frequency supported by AT45DB321D-MWU for continuous array reads?
The AT45DB321D-MWU supports up to 66 MHz for continuous array reads using opcodes 0BH and E8H, and up to 33 MHz using opcode 03H. These frequencies are specified under valid VCC (2.5–3.6V) and industrial temperature conditions. The actual achievable rate depends on host controller timing margins and PCB signal integrity - the device's RDY/BUSY pin provides precise busy-state visibility to prevent read collisions during self-timed operations. AT45DB321D-MWU does not require external wait states when operating within these limits.
Does AT45DB321D-MWU require high-voltage programming or external circuitry?
No, AT45DB321D-MWU operates entirely from a single 2.5V–3.6V supply for both read and program/erase functions - no VPP pin, charge pump, or external high-voltage generator is needed. All internal programming voltages are generated on-chip. This simplifies power design and eliminates risk of overvoltage damage during in-system programming. AT45DB321D-MWU achieves this through proprietary charge-pump circuitry integrated into its silicon, validated across 100,000 program/erase cycles and 20-year data retention.
How does the dual-buffer architecture of AT45DB321D-MWU improve system performance?
The AT45DB321D-MWU's two independent 512/528-byte SRAM buffers allow simultaneous data reception on SI while reprogramming flash pages - eliminating CPU polling or interrupt overhead during writes. For example, a host can stream new firmware into Buffer 1 while Buffer 2 contents are written to flash, then swap roles seamlessly. This concurrency reduces effective write latency by up to 50% versus single-buffer devices and enables deterministic real-time logging. AT45DB321D-MWU guarantees buffer-to-flash transfer completion time (tEP) under worst-case voltage/temperature conditions.
Can AT45DB321D-MWU be used as a direct replacement for standard SPI NOR flash in existing designs?
AT45DB321D-MWU is not pin-compatible or command-compatible with standard SPI NOR flash (e.g., Macronix or Winbond parts) due to its unique DataFlash command set, dual-buffer addressing, and RDY/BUSY pin usage. While both use SPI clocks and share CS/SI/SO pins, AT45DB321D-MWU requires firmware adaptation for buffer management, sector lockdown, and continuous-read opcodes. It is best suited for new designs prioritizing streaming efficiency and security over drop-in replacement - not retrofitting legacy NOR-based systems.
What security mechanisms does AT45DB321D-MWU provide for firmware protection?
AT45DB321D-MWU provides three hardware-enforced security layers: (1) individual sector write protection controlled by a dedicated sector protection register, (2) sector lockdown - irreversible hardware lock preventing any further modification to selected sectors, and (3) a 128-byte security register containing 64 bytes of user-programmable space and a unique 64-byte device identifier. These features operate independently of software commands and remain active even when WP is asserted. AT45DB321D-MWU's security model is validated for secure bootloader and trusted firmware partitioning in industrial control applications.
AT45DB321D-MWU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 8-VDFN Exposed Pad
- Packaging:
- Tray
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- FLASH
- Technology:
- FLASH
- Memory Size:
- 32Mbit
- Memory Organization:
- 528 Bytes x 8192 pages
- Memory Interface:
- SPI
- Clock Frequency:
- 66 MHz
- Write Cycle Time - Word, Page:
- 6ms
- Access Time:
- -
- Voltage - Supply:
- 2.7V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-VDFN (8x6)
AT45DB321D-MWU FAQ
1.How can I place an order for AT45DB321D-MWU through Aetrix?
Please submit a Request for Quotation (RFQ) for AT45DB321D-MWU 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 AT45DB321D-MWU reliable?
The price and inventory of AT45DB321D-MWU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT45DB321D-MWU is usually 5 days.
3.What payment methods are accepted for AT45DB321D-MWU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT45DB321D-MWU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT45DB321D-MWU?
AT45DB321D-MWU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT45DB321D-MWU 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 AT45DB321D-MWU?
For technical support, including AT45DB321D-MWU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT45DB321D-MWU requirements.
6.How does Aetrix verify that AT45DB321D-MWU is sourced from the original manufacturer or authorized distributors?
All AT45DB321D-MWU 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 AT45DB321D-MWU meets industry standards.
7.What is the process for return or replacement of AT45DB321D-MWU?
All AT45DB321D-MWU units undergo pre-shipment inspection (PSI). If there is an issue with AT45DB321D-MWU, 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 AT45DB321D-MWU part is unused and in its original packaging.
Return procedure for AT45DB321D-MWU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT45DB321D-MWU Tags
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