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Renesas AT45DB321D-CU
- Part No.:
- AT45DB321D-CU
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 24-TBGA, CSPBGA
- Datasheet:
-
AT45DB321D-CU.pdf
- Description:
- IC FLASH 32MBIT SPI 66MHZ 24CBGA
- Quantity:
- Payment:
- Shipping:
Inventory:4,938
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Product details
Overview
AT45DB321D-CU 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 continuous array read capability up to 66MHz - ideal for code shadowing in embedded microcontroller boot systems.
For engineers reviewing the AT45DB321D-CU datasheet, AT45DB321D-CU pinout, AT45DB321D-CU application, or AT45DB321D-CU equivalent, key selection considerations include its 2.5V–3.6V single-supply operation, page/block/sector/chip erase flexibility, hardware write protection (WP), RDY/BUSY status signaling, and industrial temperature range support.
Technical Context
The AT45DB321D-CU 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 continuous read opcodes (03H, 0BH, E8H) optimized for different speed and dummy-cycle requirements.
Memory organization includes hierarchical erasability: page (512 B), block (4KB = 8 pages), sector (64KB), and full chip (32Mb). Page programming supports both built-in erase (83H/86H) and no-erase (88H/89H) modes, while sector lockdown and a 128-byte security register provide hardware-enforced data integrity.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Capacity | 32Mb (34,603,008 bits), organized as 8,192 pages × 512 or 528 bytes - enables flexible firmware/image storage with byte-addressable buffer access. |
| Interface Speed | Up to 66MHz SCK for continuous reads (0BH/E8H), 33MHz for low-frequency mode (03H) - supports real-time streaming without CPU polling overhead. |
| Supply Voltage | 2.5V–3.6V or 2.7V–3.6V single supply - compatible with modern low-voltage MCUs and eliminates need for charge pumps or auxiliary rails. |
| Power Consumption | 7mA typical active read current; 25µA standby; 15µA deep power-down - suitable for battery-backed or energy-constrained IoT endpoints. |
| Erase Endurance | 100,000 program/erase cycles per page minimum - ensures long-term reliability in field-upgradable firmware storage applications. |
| Data Retention | 20 years at +85°C - validated for industrial deployments requiring multi-decade data integrity without refresh. |
| Operating Temp | −40°C to +85°C industrial range - qualified for automotive infotainment head units, industrial HMIs, and outdoor telemetry nodes. |
Pinout & Package
AT45DB321D-CU is packaged in an 8-pin SOIC (Small Outline Integrated Circuit) with standard 150-mil body width and RoHS-compliant green finish. Pin functions are electrically defined and validated per Atmel datasheet 3597Q–DFLASH–6/11.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-low enable; must transition high-to-low to initiate commands and low-to-high to complete self-timed operations (e.g., erase). |
| SCK | Serial Clock | Input clock controlling data latching (SI on rising edge) and output timing (SO on falling edge); supports up to 66MHz. |
| SI | Serial Input | Command, address, and data input line; MSB-first protocol; used for all host-to-device communication. |
| SO | Serial Output | Data output line; tri-stated when CS is high; outputs status, memory/buffer contents, or device IDs. |
| WP | Write Protect | Hardware-level sector lockout; low-active signal that overrides software protection - critical for secure bootloader partitions. |
| RESET | Reset Input | Active-low asynchronous reset; terminates ongoing operations and returns state machine to idle - used for recovery after bus errors. |
| RDY/BUSY | Open-drain Status | Drives low during internal self-timed operations (program/erase/buffer transfers); requires external pull-up for host polling or interrupt use. |
| VCC / GND | Power Supply | Single 2.5–3.6V supply with dedicated ground; decoupling capacitor required near VCC pin for stable high-speed operation. |
Key Features
| Feature | Design Value |
|---|---|
| Dual SRAM Buffers | Two independent 512/528-byte buffers enable simultaneous data streaming into one buffer while programming the other to flash - eliminates write latency bottlenecks. |
| Flexible Page Size | User-configurable 512-byte (binary-aligned) or 528-byte (DataFlash-optimized) pages - balances compatibility with legacy systems and efficient ECC/data overhead handling. |
| Multi-Level Erase | Page (512B), block (4KB), sector (64KB), and chip (32Mb) erase options - allows precise wear leveling and partial firmware updates without full reflash. |
| Hardware Security | 128-byte security register (64B user-programmable + 64B unique device ID) plus sector lockdown - prevents unauthorized firmware extraction or modification in certified devices. |
| JEDEC ID Support | Standard manufacturer (0x1F) and device (0x26) ID read - enables automatic part identification and BOM validation during production programming. |
Applications
| Firmware Boot Storage | Industrial Data Logger |
|---|---|
Use Scenario: Storing compressed application firmware loaded by an MCU at power-on for execution in external RAM. IC Role / Device Role / Timing Role: Nonvolatile code repository with continuous read capability enabling zero-wait-state shadowing into XIP-capable RAM. Use Value: Eliminates need for parallel NOR flash; reduces PCB footprint and signal count while maintaining 66MHz read throughput for fast boot times. | Use Scenario: Capturing sensor readings (temperature, pressure, vibration) over extended periods in remote monitoring stations. IC Role / Device Role / Timing Role: High-endurance sequential data sink with sector-locked configuration protecting calibration tables and firmware partitions. Use Value: 100,000 erase cycles per page and 20-year retention ensure reliable decade-long deployment without maintenance. |
| Secure OTA Update Module | Medical Imaging Buffer |
Use Scenario: Hosting signed firmware images and cryptographic keys for authenticated over-the-air updates in connected medical devices. IC Role / Device Role / Timing Role: Secure storage element with hardware write protection and sector lockdown isolating trusted update payload from runtime code. Use Value: Prevents rollback attacks and unauthorized writes via WP pin assertion - meets IEC 62304 Class C software safety requirements. | Use Scenario: Temporary buffering of ultrasound or endoscopic image frames before compression and transmission to host processor. IC Role / Device Role / Timing Role: High-bandwidth sequential memory with dual-buffer ping-pong operation supporting real-time frame capture at >20MB/s effective rate. Use Value: Concurrent buffer fill and flash write avoids frame drop during burst acquisition - enabled by independent SRAM buffer arbitration. |
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 (QSPI) interface; 133MHz clock; no dual SRAM buffers; standard 4KB sectors only. | Lacks continuous read and buffer concurrency; requires software-managed erase scheduling instead of hardware-accelerated page/block/sector options. | Choose for QSPI host compatibility and higher clock rates where buffer concurrency is unnecessary. |
| Macronix MX25L3233FZNI-10G | 32Mb standard SPI; 104MHz max; no SRAM buffers; 4KB/32KB/64KB erase blocks; no sector lockdown or security register. | No hardware security features; lacks RDY/BUSY pin - requires command polling; no continuous read mode for streaming. | Choose for cost-sensitive designs needing basic SPI flash without advanced data integrity or streaming features. |
Compared with W25Q32JVSSIQ and MX25L3233FZNI-10G, the AT45DB321D-CU uniquely delivers concurrent buffer operation, hardware sector lockdown, and three-tiered erase granularity - making it optimal for secure, streaming-intensive embedded firmware storage where deterministic latency and data isolation are mandatory.
Availability
AT45DB321D-CU is available at Aetrix Electronics and suitable for firmware boot storage, industrial data logging, secure OTA update modules, and medical imaging buffer applications requiring stable component supply across long-lifecycle programs.
Supply support for AT45DB321D-CU 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 product support, documentation, and manufacturing continuity for the AT45DB321D-CU.
The AT45DB321D-CU belongs to the Atmel DataFlash family - designed specifically for high-reliability, low-pin-count serial flash applications demanding concurrent buffer access, flexible erase granularity, and hardware-enforced security in resource-constrained embedded systems.
FAQ
What voltage range does the AT45DB321D-CU support?
The AT45DB321D-CU operates from a single supply of 2.5V–3.6V or 2.7V–3.6V, eliminating the need for multiple voltage rails or charge pumps. This range ensures compatibility with modern 3.3V and mixed-voltage microcontroller systems while maintaining full specification compliance across the entire operating window. The AT45DB321D-CU's internal regulation and timing circuits are fully characterized within this range.
Does the AT45DB321D-CU support true SPI mode compatibility?
Yes, the AT45DB321D-CU supports SPI modes 0 and 3 per the standard SPI specification, with data sampled on the rising edge of SCK (SI) and shifted out on the falling edge (SO). Its Atmel RapidS interface extends standard SPI with higher clock rates (up to 66MHz) and additional opcodes for continuous read and buffer management - all while maintaining electrical and protocol interoperability with conventional SPI controllers.
How does the dual-buffer architecture of the AT45DB321D-CU improve system performance?
The AT45DB321D-CU integrates two independent 512/528-byte SRAM buffers that operate asynchronously from the main flash array. This allows a host processor to stream new data into one buffer while the other buffer's contents are being programmed into flash - eliminating write stalls and enabling sustained data throughput. The AT45DB321D-CU's buffer-to-page programming commands (83H/86H) execute internally without host intervention.
Can the AT45DB321D-CU be used for secure firmware storage?
Yes, the AT45DB321D-CU includes hardware-based security features essential for secure firmware storage: a 128-byte security register (64B user-programmable + 64B unique device ID), individual sector lockdown, and hardware write protection (WP pin) that overrides all software commands. These features allow partitioning of bootloader, application, and calibration data with physical write disable - directly supporting IEC 62304 and ISO 13849 functional safety requirements. The AT45DB321D-CU's security model is implemented in silicon and cannot be bypassed via software.
What erase options are available on the AT45DB321D-CU?
The AT45DB321D-CU provides four granular erase options: page (512 bytes), block (4KB = 8 pages), sector (64KB), and full chip (32Mb). Each uses distinct opcodes (81H, 50H, 7CH, C7H+94H+80H+9AH) and has independently specified maximum times (tPE, tBE, tSE, tCE). This hierarchy enables precise wear leveling, partial firmware updates, and rapid recovery from corruption - unlike uniform-sector flash devices. All erase operations are internally self-timed and signaled via RDY/BUSY pin or status register polling.
AT45DB321D-CU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 24-TBGA, CSPBGA
- 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:
- 24-CBGA (6x8)
AT45DB321D-CU FAQ
1.How can I place an order for AT45DB321D-CU through Aetrix?
Please submit a Request for Quotation (RFQ) for AT45DB321D-CU 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-CU reliable?
The price and inventory of AT45DB321D-CU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT45DB321D-CU is usually 5 days.
3.What payment methods are accepted for AT45DB321D-CU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT45DB321D-CU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT45DB321D-CU?
AT45DB321D-CU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT45DB321D-CU 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-CU?
For technical support, including AT45DB321D-CU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT45DB321D-CU requirements.
6.How does Aetrix verify that AT45DB321D-CU is sourced from the original manufacturer or authorized distributors?
All AT45DB321D-CU 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-CU meets industry standards.
7.What is the process for return or replacement of AT45DB321D-CU?
All AT45DB321D-CU units undergo pre-shipment inspection (PSI). If there is an issue with AT45DB321D-CU, 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-CU part is unused and in its original packaging.
Return procedure for AT45DB321D-CU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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