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Renesas AT45DB321D-MU
- Part No.:
- AT45DB321D-MU
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 8-VDFN Exposed Pad
- Datasheet:
-
AT45DB321D-MU.pdf
- Description:
- IC FLASH 32MBIT SPI 66MHZ 8VDFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,899
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Product details
Overview
AT45DB321D-MU from Microchip Technology (formerly Atmel) is a 32Mb serial DataFlash memory IC with SPI-compatible RapidS interface, organized as 8,192 pages of 512/528 bytes each, featuring dual 512/528-byte SRAM buffers and hardware write protection. It operates from a single 2.5V–3.6V supply, supports up to 66MHz clock frequency, and delivers 7mA typical active read current for embedded code shadowing and firmware storage applications.
For engineers reviewing the AT45DB321D-MU datasheet, AT45DB321D-MU pinout, AT45DB321D-MU application, or AT45DB321D-MU equivalent, key selection considerations include page size configurability (512 vs. 528 bytes), sector lockdown security, continuous array read capability, and industrial temperature operation without high-voltage programming.
Technical Context
The AT45DB321D-MU implements a sequential-access flash architecture with two independent 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 includes hierarchical erase granularity-page (512 B), block (4KB), sector (64KB), and chip (32Mb)-with self-timed program/erase cycles and RDY/BUSY status reporting via open-drain output. Page size is factory-configurable and determines address bit mapping (PA12–PA0/BA9–BA0 for 528B; A21–A0 for 512B), directly affecting host software addressing logic.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory density | 32Mb (4MB) total capacity, organized as 8,192 pages × 512 or 528 bytes |
| Interface speed | Up to 66MHz SCK for continuous reads (0BH/E8H), enabling >8MB/s sustained throughput |
| Supply voltage | 2.5V–3.6V single supply; no external VPP required for programming or erase |
| Power consumption | 7mA typical active read current; 25µA standby; 15µA deep power-down mode |
| Erase endurance | 100,000 program/erase cycles per page minimum, ensuring long-term field reliability |
| Data retention | 20 years at industrial temperature range (–40°C to +85°C) |
| Security features | 128-byte security register (64-byte user-programmable + 64-byte unique ID) and sector lockdown |
Pinout & Package
AT45DB321D-MU is packaged in an 8-pin MLF (VDFN) with exposed thermal pad (floating or GND-connected). Pin functions are electrically identical across SOIC, TSOP, and BGA variants but physically mapped to this compact 3mm × 3mm leadless package.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-low enable; falling edge initiates command sequence; device enters standby on deassertion |
| SCK | Serial Clock | Input clock controlling data latching (SI on rising edge) and output timing (SO on falling edge) |
| SI | Serial Input | Command, address, and data input path; MSB-first protocol with no internal buffering |
| SO | Serial Output | Open-drain-capable output for data, status, or ID reads; tri-stated when CS is high |
| WP | Write Protect | Hardware-level sector lock override; low state blocks all protected-sector writes regardless of software settings |
| RESET | Reset | Active-low hard reset; terminates ongoing operations and returns state machine to idle |
| RDY/BUSY | Ready/Busy Status | Open-drain output pulled high externally; driven low during self-timed program/erase/page-transfer |
| VCC / GND | Power Supply | Single 2.5V–3.6V supply; GND serves as reference for all I/O and internal circuitry |
Key Features
| Feature | Design Value |
|---|---|
| Dual SRAM buffers | Two independent 512/528-byte buffers enable simultaneous data streaming into one buffer while reprogramming flash from the other |
| Continuous array read | Three opcodes (03H/0BH/E8H) support seamless wraparound reads across page and array boundaries without host address updates |
| Flexible erase hierarchy | Four granular erase options (page/block/sector/chip) allow precise wear leveling and firmware update partitioning |
| Factory-configurable page size | 512-byte (power-of-two) or 528-byte (standard DataFlash) mode selected at manufacture, defining address bit layout and buffer usage |
| Hardware + software protection | WP pin provides unconditional sector lock; sector protection register enables selective software-based write/erase disable |
Applications
| Firmware Storage | Code Shadowing |
|---|---|
|
Use Scenario: Storing boot firmware, bootloader, or field-upgradable application binaries in microcontroller-based systems. IC Role / Device Role / Timing Role: Nonvolatile storage medium accessed via SPI during cold start or OTA update sequences. Use Value: Eliminates need for parallel NOR flash or external EEPROM; 20-year data retention ensures long-life deployment without refresh. |
Use Scenario: Copying executable code from flash to RAM at system startup for faster execution. IC Role / Device Role / Timing Role: High-speed sequential memory source feeding instruction cache or DMA controller. Use Value: Continuous array read at 66MHz enables rapid shadowing of multi-kilobyte code segments with zero inter-page latency. |
| Secure Configuration Storage | Industrial Data Logging |
|
Use Scenario: Storing calibrated sensor parameters, cryptographic keys, or device-specific credentials in tamper-resistant memory. IC Role / Device Role / Timing Role: Secure nonvolatile register bank leveraging sector lockdown and 128-byte security register. Use Value: Hardware-enforced sector protection prevents unauthorized overwrite even if host MCU is compromised. |
Use Scenario: Buffering time-stamped sensor readings or event logs in remote monitoring equipment operating unattended for months. IC Role / Device Role / Timing Role: Low-power persistent storage with deep power-down mode (15µA) extending battery life. Use Value: Dual-buffer architecture allows background logging to one buffer while host processes prior data from the other. |
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, 133MHz DTR mode; no SRAM buffers or continuous read wraparound | Better random access performance; lacks built-in EEPROM emulation and dual-buffer streaming capability | Select for systems requiring fast XIP or byte-addressable writes; not drop-in for DataFlash buffer workflows |
| Macronix MX25L3233FZUI | 32Mb standard SPI NOR flash; 104MHz max clock; no configurable page size or sector lockdown security register | Lower cost; supports basic firmware storage but lacks security features and intelligent programming operations | Choose when sector-level protection and 20-year retention are non-critical; requires host-side EEPROM emulation |
Compared with AT45DB321D-MU, W25Q32JVSSIQ offers higher bandwidth for random reads but no dual-buffer streaming or automatic page-wrap reads, while MX25L3233FZUI omits hardware security and buffer-assisted programming-making AT45DB321D-MU uniquely suited for secure, streaming-centric embedded storage where sequential throughput and data integrity are prioritized over raw random-access speed.
Availability
AT45DB321D-MU is available at Aetrix Electronics and suitable for firmware storage, code shadowing, secure configuration storage, and industrial data logging requiring stable component supply across extended product lifecycles.
Supply support for AT45DB321D-MU 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 legacy qualification and long-term manufacturing commitments.
The AT45DB321D-MU belongs to the Atmel DataFlash® series, designed specifically for high-reliability, low-pin-count serial flash applications demanding concurrent read/write, security, and industrial-grade endurance.
FAQ
What is the default page size configuration for AT45DB321D-MU?
The AT45DB321D-MU is factory-configured for 528-byte pages, which includes 16 bytes of overhead per page for ECC and metadata. This configuration enables the full 528-byte buffer utilization and uses PA12–PA0/BA9–BA0 addressing. The 512-byte mode is available only on specific ordering options and requires matching host firmware addressing logic.
Does AT45DB321D-MU support true byte-level writes like EEPROM?
No, AT45DB321D-MU does not support true byte-level writes. However, it enables EEPROM emulation through a self-contained three-step read-modify-write operation managed entirely by the host processor-leveraging its dual buffers to minimize latency and avoid external RAM buffering.
Can AT45DB321D-MU be used without connecting the RESET pin?
Yes, AT45DB321D-MU incorporates an internal power-on reset circuit, so the RESET pin may be left unconnected or tied externally to VCC if system-level reset control is unnecessary. The device will initialize correctly on power-up without external RESET assertion.
How does the RDY/BUSY pin behave during a buffer-to-main-memory page program?
During a buffer-to-main-memory page program (opcodes 83H/86H), the RDY/BUSY pin is actively driven low for the entire duration-including both the erase and programming phases-and returns high only after completion. This signal is essential for host synchronization and eliminates the need for polling status registers.
Is the exposed metal pad on the bottom of the AT45DB321D-MU MLF package required to be grounded?
No, the exposed thermal pad on the AT45DB321D-MU MLF package is floating by default and may be left unconnected. It can optionally be connected to GND to improve thermal dissipation and reduce noise coupling-but doing so requires careful PCB layout to avoid shorting adjacent traces, as no internal connection exists.
AT45DB321D-MU 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 (6x5)
AT45DB321D-MU FAQ
1.How can I place an order for AT45DB321D-MU through Aetrix?
Please submit a Request for Quotation (RFQ) for AT45DB321D-MU 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-MU reliable?
The price and inventory of AT45DB321D-MU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT45DB321D-MU is usually 5 days.
3.What payment methods are accepted for AT45DB321D-MU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT45DB321D-MU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT45DB321D-MU?
AT45DB321D-MU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT45DB321D-MU 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-MU?
For technical support, including AT45DB321D-MU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT45DB321D-MU requirements.
6.How does Aetrix verify that AT45DB321D-MU is sourced from the original manufacturer or authorized distributors?
All AT45DB321D-MU 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-MU meets industry standards.
7.What is the process for return or replacement of AT45DB321D-MU?
All AT45DB321D-MU units undergo pre-shipment inspection (PSI). If there is an issue with AT45DB321D-MU, 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-MU part is unused and in its original packaging.
Return procedure for AT45DB321D-MU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT45DB321D-MU Tags
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AT24C02C-XHM-T
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