Part A
AT45DB161D-TU
Adesto Technologies
- Lifecycle
- Active
- Stock
- 7667 PCS
- Package
- TSSOP-28
- Series
- Memory
Replacement verdict
Not a drop-in replacement
The AT45DB161D-TU and AT45DB321C-TC differ in memory density, page size, package type, and supply voltage range, so they are not functionally interchangeable in existing designs. The AT45DB321C-TC offers twice the density but requires a different footprint and voltage considerations, meaning a direct board-level swap is not possible without redesign.
Different memory density
Different page size
Different package type
Different supply voltage range
Parts at a glance
Part B
AT45DB321C-TC
Microchip Technology
- Lifecycle
- Active
- Stock
- 6459 PCS
- Package
- TSSOP-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-TC | Why it matters |
|---|---|---|---|
| Memory Density | 16 Mbit (2 MB) | 32 Mbit (4 MB) | Density determines total storage capacity; a 32 Mbit device stores 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 address range; differing counts require address map changes 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 allow the same power design to be reused. |
| Maximum Clock Frequency (SPI) | 66 MHz | 50 MHz | Clock rate sets maximum data throughput; a slower device may bottleneck high-speed read/write operations in the same socket. |
| Package / Mounting | 28-pin TSOP (surface mount) | 28-pin TSOP (surface mount) | Package and pinout must match the PCB footprint; identical TSOP-28 packages allow physical drop-in compatibility. |
| Interface Type | SPI (Serial Peripheral Interface) | SPI (Serial Peripheral Interface) | A shared SPI interface means the same host controller and driver architecture can communicate with either device. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Temperature range determines suitability for industrial versus commercial environments; matching ranges preserve application scope. |
| Data Retention | 20 years (typical) | 20 years (typical) | Retention guarantees long-term data integrity in non-volatile storage; equivalent retention supports comparable reliability expectations. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AT45DB161D-TU | AT45DB321C-TC |
|---|---|---|
| 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) | 0°C ~ 70°C (TC) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the key differences between the AT45DB161D-TU and AT45DB321C-TC?
The AT45DB161D-TU is a 16-Mbit (2-Mbyte) DataFlash memory device in a 28-lead TSOP package, while the AT45DB321C-TC is a 32-Mbit (4-Mbyte) DataFlash device in a 28-lead TSOP package. The primary differences are memory density (16 Mbit vs 32 Mbit) and the specific datasheet-defined page size and interface timing characteristics of each series.
Are the AT45DB161D-TU and AT45DB321C-TC pin-compatible?
Both devices are offered in a 28-lead TSOP package, but pin compatibility must be confirmed against the respective manufacturer datasheets. The AT45DB161D and AT45DB321C belong to different DataFlash generations, so designers should verify pin functions and signal assignments before considering a board-level swap.
What is the memory density of each device?
The AT45DB161D-TU provides 16 Mbits (2 Mbytes) of serial DataFlash memory. The AT45DB321C-TC provides 32 Mbits (4 Mbytes). The AT45DB321C-TC therefore offers twice the storage capacity of the AT45DB161D-TU.
What serial interface do these DataFlash devices use?
Both the AT45DB161D and AT45DB321C are Serial Peripheral Interface (SPI) compatible DataFlash devices, supporting standard SPI modes for connection to microcontrollers and other host processors. Designers should consult the respective datasheets for maximum clock frequency and mode support.
Can the AT45DB321C-TC be used as a drop-in replacement for the AT45DB161D-TU?
No. Although both are 28-lead TSOP DataFlash devices, they differ in memory density and belong to different product generations. A drop-in replacement requires verification of package dimensions, pin functions, command set compatibility, page size, and timing against both datasheets, and the host firmware must be updated to address the larger memory array.
Do these devices support page erase and program operations?
Yes. Both the AT45DB161D and AT45DB321C DataFlash families support page program and page erase operations as defined in their respective datasheets. The exact page size and number of pages differ between the 16-Mbit and 32-Mbit densities and must be confirmed from the manufacturer documentation.
What supply voltage do the AT45DB161D-TU and AT45DB321C-TC require?
Both devices are specified for a 2.7 V to 3.6 V supply range per their manufacturer datasheets. Designers should confirm the exact operating voltage and current specifications from the official datasheet for the specific grade and package option being used.