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Renesas AT45DB642D-CNU-SL955
- Part No.:
- AT45DB642D-CNU-SL955
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 8-VDFN
- Datasheet:
-
AT45DB642D-CNU-SL955.pdf
- Description:
- IC FLASH 64MBIT SPI 66MHZ 8CASON
- Quantity:
- Payment:
- Shipping:
Inventory:1,234
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Product details
Overview
AT45DB642D-CNU-SL955 from Microchip Technology is a 64-Mbit (69,206,016-bit), dual-interface DataFlash memory IC supporting both RapidS™ SPI-compatible serial interface (up to 66 MHz) and Rapid8™ 8-bit parallel interface (up to 50 MHz), with user-configurable 1024- or 1056-byte page size, two 1024/1056-byte SRAM buffers, and industrial temperature range (−40°C to +85°C). It enables code shadowing, firmware storage, and data logging in resource-constrained embedded systems.
For engineers reviewing the AT45DB642D-CNU-SL955 datasheet, AT45DB642D-CNU-SL955 pinout, AT45DB642D-CNU-SL955 application, or AT45DB642D-CNU-SL955 equivalent, key selection considerations include dual-interface flexibility, buffer-assisted concurrent read/write operation, sector-level hardware write protection, 100,000 program/erase cycles, and green RoHS-compliant packaging.
Technical Context
The AT45DB642D-CNU-SL955 implements a sequential-access Flash architecture with no address bus-data is accessed via command-driven protocols over either SPI (Mode 0/3) or 8-bit parallel interface. Its memory is organized as 8,192 pages (1024- or 1056-byte configurable), divided into 32 sectors of 256 pages each, enabling granular erase control at page (1 KB), block (8 KB), sector (256 KB), or chip (64 Mbit) level.
Two independent 1024/1056-byte SRAM buffers support pipelined operation: while one buffer receives new data via SI/I/O pins, the other can simultaneously program a full page into Flash or serve as a temporary data staging area. All programming and erase operations are fully self-timed with RDY/BUSY pin indication and require no external high-voltage supply.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 64 Mbit (69,206,016 bits), organized as 8,192 × (1024 or 1056)-byte pages |
| Supply Voltage | 2.7V–3.6V single supply-enables direct integration with 3.3V logic without level shifters |
| RapidS Interface Speed | Up to 66 MHz clock-supports high-throughput streaming reads (e.g., audio/video buffering) |
| Rapid8 Interface Speed | Up to 50 MHz clock-delivers ~400 MB/s peak bandwidth for microcontroller-side burst transfers |
| SRAM Buffers | Two independent 1024/1056-byte buffers-enable true overlap of data reception and Flash programming |
| Erase Endurance | ≥100,000 program/erase cycles per page-validated for long-life firmware update partitions |
| Data Retention | 20 years at +85°C-guarantees reliability in industrial thermal environments |
| Power Consumption | 10 mA active read (typ), 25 µA standby (typ), 15 µA deep power-down (typ)-optimized for battery-backed systems |
Pinout & Package
AT45DB642D-CNU-SL955 is packaged in a 28-pin TSOP-I (Type 1) with 0.55 mm pitch, pin-compatible with industry-standard JEDEC MO-153. The package supports both serial and 8-bit interface modes via SER/BYTE pin control and includes dedicated VCCP/GNDP pins for isolated 8-bit I/O power when used.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-low enable-starts/ends all commands; deassertion places device in standby (not deep power-down) |
| SCK/CLK | Serial Clock / 8-bit Clock | Unified clock input-rising edge latches input (SI or I/O7–I/O0); falling edge clocks out SO or I/O7–I/O0 |
| SI | Serial Input | Command/address/data input for RapidS mode; NC when SER/BYTE = low |
| SO | Serial Output | Data output for RapidS mode; tri-stated when SER/BYTE = low |
| I/O7–I/O0 | 8-bit Bidirectional Data Bus | Parallel command/address/data transfer in Rapid8 mode; high-impedance when SER/BYTE = high |
| WP | Hardware Write Protect | Low-active pin-overrides software protection to lock selected sectors against accidental program/erase |
| RESET | Asynchronous Reset | Low-active-aborts ongoing operation and resets internal state machine; internal POR eliminates external RC need |
| RDY/BUSY | Open-Drain Status Indicator | Drives low during self-timed operations (program/erase/buffer transfer)-enables polling or interrupt-driven flow control |
| SER/BYTE | Interface Mode Select | High = RapidS only (SI/SO active); Low = Rapid8 only (I/O7–I/O0 active); internal pull-up allows serial-only use with NC |
| VCC / GND | Core Power / Ground | 2.7–3.6V main supply; decoupling required within 1 cm of pins for noise-sensitive timing |
| VCCP / GNDP | 8-bit I/O Power / Ground | Required only when using Rapid8 interface; enables independent voltage domain for mixed-signal isolation |
Key Features
| Feature | Design Value |
|---|---|
| Dual-interface architecture | Simultaneous RapidS (SPI) and Rapid8 (8-bit) ports allow DSP-to-serial + MCU-to-parallel connectivity without multiplexing overhead |
| Configurable page size | Factory-set 1024-byte (binary) or 1056-byte (standard DataFlash) pages-optimizes alignment for legacy firmware or byte-addressable EEPROM emulation |
| Buffer-assisted pipelining | Two independent SRAM buffers enable continuous data streaming: receive new data into one buffer while programming the other into Flash |
| Hardware sector lockdown | Permanent, irreversible locking of individual sectors-secures boot code or calibration data against field corruption or malicious overwrite |
| 128-byte security register | Includes 64-byte user-programmable space + 64-byte unique device ID-supports secure provisioning and anti-cloning in production |
| Continuous array read | Legacy (E8H), high-speed (0BH), and low-overhead (03H) read modes-eliminates address retransmission across page boundaries for seamless streaming |
Applications
| Industrial Firmware Storage | Audio Voice Logging |
|---|---|
Use Scenario: Storing and updating bootloader, application firmware, and configuration parameters in programmable logic controllers (PLCs) and motor drives. IC Role / Device Role / Timing Role: Nonvolatile firmware repository with in-system reprogrammability via serial or parallel host interface. Use Value: Enables field firmware upgrades without removing the device; 100,000-cycle endurance supports >10 years of quarterly updates at 25 cycles/year. | Use Scenario: Capturing and replaying voice prompts, alarm tones, and diagnostic audio in medical devices and building automation panels. IC Role / Device Role / Timing Role: High-bandwidth sequential audio buffer with zero-gap playback across page boundaries. Use Value: Continuous Array Read (0BH/E8H) delivers uninterrupted 66 MHz streaming-eliminates audio dropouts during page wraparound. |
| Secure Boot Code Storage | Embedded Data Logger |
Use Scenario: Holding immutable boot code and cryptographic keys in payment terminals and IoT gateways requiring FIPS-aligned secure boot. IC Role / Device Role / Timing Role: Tamper-resistant code vault leveraging permanent sector lockdown and unique device ID. Use Value: Hardware-enforced sector lockdown prevents runtime modification; 64-byte device ID enables per-unit key binding in secure provisioning flows. | Use Scenario: Recording sensor telemetry (temperature, pressure, vibration) in environmental monitoring nodes operating on coin-cell batteries. IC Role / Device Role / Timing Role: Low-power nonvolatile data sink supporting intermittent writes and long-term retention. Use Value: 15 µA deep power-down current extends 10-year battery life; 20-year data retention ensures archival integrity without refresh. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial/parallel Flash memory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AT45DB642D-SU | Same die, 8-pin SOIC package (no VCCP/GNDP, no I/O7–I/O0 pins); lacks Rapid8 interface | Restricted to SPI-only systems; unsuitable for high-bandwidth parallel host connections | Select when board space is constrained and only serial interface is needed-reduces pin count and layout complexity. |
| W25Q64JVSSIQ | 64 Mbit Quad SPI NOR Flash; no parallel interface, no SRAM buffers, no page-size configurability | Requires external buffering for streaming; no built-in EEPROM emulation capability | Select for cost-sensitive, SPI-only designs where continuous read performance and buffer-assisted writes are not required. |
Compared with AT45DB642D-SU, the AT45DB642D-CNU-SL955 adds Rapid8 support and isolated I/O power-critical for mixed-signal MCU coexistence. Versus W25Q64JVSSIQ, it provides true concurrent read/write via dual buffers and flexible erase granularity, but at higher pin count and BOM cost.
Availability
AT45DB642D-CNU-SL955 is available at Aetrix Electronics and suitable for industrial firmware storage, audio voice logging, secure boot code storage, and embedded data logging requiring stable component supply across extended product lifecycles.
Supply support for AT45DB642D-CNU-SL955 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 is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, Flash memory, and security ICs, with broad industrial and automotive qualification coverage.
The AT45DB642D-CNU-SL955 belongs to Microchip's DataFlash® family-designed specifically for high-reliability, low-pin-count, dual-interface nonvolatile storage in embedded systems where sequential access, buffer-assisted throughput, and hardware security are critical.
FAQ
What interfaces does the AT45DB642D-CNU-SL955 support, and how are they selected?
The AT45DB642D-CNU-SL955 supports both RapidS™ (SPI-compatible serial) and Rapid8™ (8-bit parallel) interfaces. Selection is controlled by the SER/BYTE pin: high enables RapidS (SI/SO active), low enables Rapid8 (I/O7–I/O0 active). VCCP/GNDP must be powered only when using Rapid8. This dual-mode design allows flexible host connectivity-e.g., connecting SPI to a DSP and parallel I/O to an MCU on the same board-without requiring external multiplexers or protocol translation.
How does the AT45DB642D-CNU-SL955 handle page size configuration?
The AT45DB642D-CNU-SL955 supports two page sizes: 1024 bytes (binary) and 1056 bytes (standard DataFlash). The size is factory-configured and fixed per unit-AT45DB642D-CNU-SL955 is shipped with 1024-byte pages. This setting determines address mapping (A22–A0 vs. PA12–PA0/BA10–BA0) and buffer addressing (BFA9–BFA0 vs. BFA10–BFA0), affecting firmware compatibility. Users must align driver logic to the configured page size; no runtime switching is supported.
What is the purpose of the two SRAM buffers in the AT45DB642D-CNU-SL955?
The AT45DB642D-CNU-SL955 integrates two independent 1024/1056-byte SRAM buffers to enable concurrent operations: one buffer can receive incoming data via SI or I/O7–I/O0 while the other is being programmed into Flash memory. This pipelining eliminates idle time during page programming (tEP ≈ 20 ms), allowing continuous data streams-essential for real-time logging or audio buffering. Buffers also support EEPROM emulation via internal read-modify-write sequences without host intervention.
Does the AT45DB642D-CNU-SL955 support hardware write protection, and how is it implemented?
Yes, the AT45DB642D-CNU-SL955 supports hardware write protection via the WP (Write Protect) pin. When WP is driven low, all sectors marked in the Sector Protection Register are locked against program and erase-even if software protection is disabled. WP operates independently of software commands and cannot be overridden. The pin is internally pulled high, so it may be left unconnected for unprotected operation, but tying it to VCC is recommended unless hardware-level lockdown is required for safety-critical firmware partitions.
What are the key timing specifications for continuous read operations on the AT45DB642D-CNU-SL955?
The AT45DB642D-CNU-SL955 supports three continuous read modes: Legacy (E8H, up to 66 MHz), High-Frequency (0BH, up to 66 MHz, requires dummy byte), and Low-Frequency (03H, up to 33 MHz, no dummy byte). All modes auto-increment the internal address counter across page boundaries with zero latency-ensuring gapless streaming. Maximum SCK/CLK frequency depends on mode and VCC; fCAR1 = 66 MHz defines the upper limit for E8H/0BH, while fCAR2 = 33 MHz applies to 03H. These specs directly enable jitter-free audio playback and high-speed firmware shadowing.
AT45DB642D-CNU-SL955 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 8-VDFN
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- FLASH
- Technology:
- FLASH
- Memory Size:
- 64Mbit
- Memory Organization:
- 1K 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-CASON (6x8)
AT45DB642D-CNU-SL955 FAQ
1.How can I place an order for AT45DB642D-CNU-SL955 through Aetrix?
Please submit a Request for Quotation (RFQ) for AT45DB642D-CNU-SL955 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 AT45DB642D-CNU-SL955 reliable?
The price and inventory of AT45DB642D-CNU-SL955 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT45DB642D-CNU-SL955 is usually 5 days.
3.What payment methods are accepted for AT45DB642D-CNU-SL955?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT45DB642D-CNU-SL955 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT45DB642D-CNU-SL955?
AT45DB642D-CNU-SL955 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT45DB642D-CNU-SL955 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 AT45DB642D-CNU-SL955?
For technical support, including AT45DB642D-CNU-SL955 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT45DB642D-CNU-SL955 requirements.
6.How does Aetrix verify that AT45DB642D-CNU-SL955 is sourced from the original manufacturer or authorized distributors?
All AT45DB642D-CNU-SL955 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 AT45DB642D-CNU-SL955 meets industry standards.
7.What is the process for return or replacement of AT45DB642D-CNU-SL955?
All AT45DB642D-CNU-SL955 units undergo pre-shipment inspection (PSI). If there is an issue with AT45DB642D-CNU-SL955, 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 AT45DB642D-CNU-SL955 part is unused and in its original packaging.
Return procedure for AT45DB642D-CNU-SL955:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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