Part A
AT45DB161D-TU
Adesto Technologies
- Lifecycle
- Active
- Stock
- 7667 PCS
- Package
- TSSOP-28
- Series
- Memory
Replacement verdict
Compatible functional replacement candidate
The AT45DB161D-TU and AT45DB321C-RU share the same DataFlash interface family and package footprint, but differ in density and supply voltage range, so the AT45DB321C-RU can serve as a higher-capacity functional substitute only after confirming voltage compatibility and firmware density handling.
Memory Density
Validation required
Package Type
High match
Supply Voltage Range
Validation required
Interface Type
High match
Parts at a glance
Part B
AT45DB321C-RU
Công nghệ Microchip
- Lifecycle
- Active
- Stock
- 8280 PCS
- Package
- SOIC-28
- Series
- Memory
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AT45DB161D-TU | AT45DB321C-RU | Why it matters |
|---|---|---|---|
| Memory Density | 16 Mbit (2 MB) | 32 Mbit (4 MB) | Density determines total storage capacity; a 32 Mbit device holds twice the data of a 16 Mbit device, so they are not directly substitutable where capacity is fixed. |
| Page Size | 512 bytes (standard) / 528 bytes (binary) | 512 bytes (standard) / 528 bytes (binary) | Page size affects write granularity and buffer usage; matching page sizes simplifies firmware portability between the two parts. |
| Number of Pages | 4096 pages | 8192 pages | Page count combined with page size defines total array size and addressing range; different counts require adjusted address maps in firmware. |
| Supply Voltage Range | 2.7 V to 3.6 V | 2.7 V to 3.6 V | Operating voltage must match the host system rail; identical ranges mean both parts can share the same power design. |
| Maximum Clock Frequency (SPI) | 66 MHz | 50 MHz | Clock frequency sets maximum data throughput; a slower-rated part may bottleneck high-speed read/write operations. |
| Interface Type | SPI (Serial Peripheral Interface) | SPI (Serial Peripheral Interface) | Interface protocol must match the host controller; both use SPI, so bus compatibility is maintained. |
| Package / Case | 28-TSOP (8x13.4 mm) | 28-TSOP (8x13.4 mm) | Package footprint must match the PCB land pattern; identical packages allow drop-in board compatibility. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Temperature range determines suitability for industrial vs. commercial environments; matching ranges ensure equivalent environmental robustness. |
| Organization | 2 x 264-byte SRAM data buffers | 2 x 264-byte SRAM data buffers | Dual SRAM buffers enable simultaneous read-while-write operation; identical buffer architecture preserves the same programming model. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AT45DB161D-TU | AT45DB321C-RU |
|---|---|---|
| Supplier | - | Microchip Technology |
| Part Status | Obsolete | Obsolete |
| Memory Type | Non-Volatile | Non-Volatile |
| Memory Format | FLASH | FLASH |
| Technology | FLASH | FLASH |
| Memory Size | 16Mb (528 Bytes x 4096 pages) | 32Mb (528 Bytes x 8192 pages) |
| Memory Interface | SPI | SPI |
| Clock Frequency | 66 MHz | 40 MHz |
| Write Cycle Time - Word Page | 6ms | 15ms |
| Voltage - Supply | 2.7V ~ 3.6V | 2.7V ~ 3.6V |
| Operating Temperature | -40°C ~ 85°C (TC) | -40°C ~ 85°C (TC) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the AT45DB161D-TU and AT45DB321C-RU?
The AT45DB161D-TU is a 16-Mbit (2-Mbyte) DataFlash memory device, while the AT45DB321C-RU is a 32-Mbit (4-Mbyte) device. The AT45DB161D-TU is supplied in a 28-lead TSOP package (TU suffix), whereas the AT45DB321C-RU is supplied in a 28-lead TSOP package (RU suffix). Both are SPI-compatible serial flash memories from the Atmel (now Microchip) DataFlash family, but they differ in density and belong to different product generations (D versus C series).
Are the AT45DB161D-TU and AT45DB321C-RU pin-compatible?
Both devices are offered in a 28-lead TSOP package, and the DataFlash family generally maintains a consistent pinout across densities in the same package type. However, designers must verify the exact pin assignment and package drawing in the respective manufacturer datasheets before treating them as drop-in replacements, since pin functions and package dimensions should be confirmed against the official documentation for each specific part number.
What is the memory density and organization of each device?
The AT45DB161D-TU provides 16 Mbits (2,097,152 bytes) of memory, organized as 4,096 pages of 512 bytes each (or 528 bytes per page in the standard DataFlash page configuration). The AT45DB321C-RU provides 32 Mbits (4,194,304 bytes), organized as 8,192 pages of 512 bytes each. Both support page-based programming and erase operations typical of the DataFlash architecture.
What supply voltage do these devices require?
Both the AT45DB161D-TU and AT45DB321C-RU are specified for a single supply voltage range of 2.7 V to 3.6 V, consistent with the Atmel DataFlash product family. Designers should confirm the exact operating range in the respective datasheets, as the C and D series may have slightly different specified limits.
What is the maximum SPI clock frequency for each part?
The AT45DB161D supports SPI clock frequencies up to 66 MHz in the D-series specification. The AT45DB321C supports SPI clock frequencies up to 50 MHz per its datasheet. Because the maximum clock rate affects throughput and timing margins, the system clock should be validated against the specific device datasheet used in the design.
Can the AT45DB321C-RU be used as a direct replacement for the AT45DB161D-TU?
No, they are not directly interchangeable without design validation. Although both are 28-lead TSOP SPI DataFlash devices, they differ in density (32 Mbit versus 16 Mbit), maximum clock frequency, and product generation. Firmware that addresses page counts, status register behavior, and command sets must be verified against the target device datasheet before substitution.
What are the typical applications for these DataFlash devices?
Both devices are used for code storage, data logging, and firmware updates in embedded systems where serial flash with page-level erase and program capability is required. The AT45DB161D-TU (16 Mbit) suits moderate-density storage needs, while the AT45DB321C-RU (32 Mbit) provides higher capacity for applications requiring larger data or code storage. Selection depends on density, clock rate, and firmware compatibility requirements.