Part A
AT25DF081A-SSH-T
Adesto Technologies
- Lifecycle
- Active
- Stock
- 3274 PCS
- Package
- SOIC-8
- Series
- Memória
Replacement verdict
Compatible functional replacement candidate
The AT25DF041A-SHF-B is a lower-density member of the same Atmel (now Renesas) AT25DF SPI serial flash family as the AT25DF081A-SSH-T, sharing the same interface, command set, and package footprint. It can serve as a functional replacement candidate where 4 Mbit of density is sufficient, but the halved memory capacity and differing operating voltage range must be validated against the target design before substitution.
Memory Density
Validation required
Interface Type
High match
Package Type
High match
Operating Voltage
Validation required
Parts at a glance
Part B
AT25DF041A-SHF-B
Adesto Technologies
- Lifecycle
- Active
- Stock
- 3077 PCS
- Package
- SOIC-8
- Series
- Memória
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AT25DF081A-SSH-T | AT25DF041A-SHF-B | Why it matters |
|---|---|---|---|
| Memory Density | 8 Mbit (1 MB) | 4 Mbit (512 KB) | Density determines total storage capacity; a smaller density part cannot hold firmware or data sized for the larger device, so they are not directly substitutable without code/data resizing. |
| Memory Organization | 1M x 8 | 512K x 8 | The addressable word count differs, affecting address range and any software that assumes a specific number of pages or sectors. |
| Package / Case | 8-SOIC (0.154", 3.90mm width) | 8-SOIC (0.209", 5.30mm width) | Different SOIC body widths require different PCB land patterns; a footprint mismatch prevents drop-in replacement on an existing board. |
| Mounting Type | Surface Mount | Surface Mount | Both are surface-mount devices, so assembly method is compatible, though package width still differs. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Identical industrial temperature ratings mean both suit the same environmental conditions. |
| Supply Voltage | 2.7V to 3.6V | 2.7V to 3.6V | Matching voltage ranges confirm both operate from the same 3.3V rail without level shifting. |
| Interface Type | SPI (Serial Peripheral Interface) | SPI (Serial Peripheral Interface) | A common SPI interface allows reuse of the same host controller and driver, easing firmware portability. |
| Maximum Clock Frequency | 100 MHz | 70 MHz | A lower maximum clock on the 4 Mbit part may reduce read throughput and require timing adjustments in the host design. |
| Page Size | 256 Bytes | 256 Bytes | Identical page size means program/write routines and buffer sizing remain compatible between the two devices. |
| Sector Size | 4 KB | 4 KB | Matching erase-sector granularity keeps erase and wear-leveling logic unchanged across both parts. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AT25DF081A-SSH-T | AT25DF041A-SHF-B |
|---|---|---|
| Supplier | - | Dialog Semiconductor GmbH |
| Part Status | Active | Obsolete |
| Memory Type | Non-Volatile | Non-Volatile |
| Memory Format | FLASH | FLASH |
| Technology | FLASH | FLASH |
| Memory Size | 8Mb (256 Bytes x 4096 pages) | 4Mb (512K x 8) |
| Memory Interface | SPI | SPI |
| Clock Frequency | 100 MHz | 50 MHz |
| Write Cycle Time - Word Page | 7µs, 3ms | 7µs, 5ms |
| Voltage - Supply | 2.7V ~ 3.6V | 2.3V ~ 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 AT25DF081A-SSH-T and AT25DF041A-SHF-B?
The AT25DF081A-SSH-T is an 8-Mbit (1 MByte) SPI serial flash memory, while the AT25DF041A-SHF-B is a 4-Mbit (512 KByte) device. Both are part of the Adesto (formerly Atmel) AT25DF series of SPI flash memories, but they differ in density, package, and temperature grade. The AT25DF081A-SSH-T is supplied in an 8-lead SOIC package (SSH suffix) and the AT25DF041A-SHF-B is supplied in an 8-lead SOIC package (SHF suffix) with a different temperature/operating grade. Designers must confirm exact ordering codes against the respective datasheets.
Are the AT25DF081A-SSH-T and AT25DF041A-SHF-B pin-compatible?
Both devices are offered in 8-lead SOIC packages with the standard SPI flash pinout (CS, SCK, SI, SO, WP, HOLD, VCC, GND). Because they share the same package family and SPI interface, they are generally pin-compatible in terms of signal assignment. However, designers should verify the exact package drawing and land pattern from the respective datasheets before substituting one for the other.
What SPI interface and clock frequency do these devices support?
Both the AT25DF081A and AT25DF041A support the standard SPI interface (Mode 0 and Mode 3) and dual-output read capability. The AT25DF081A supports clock frequencies up to 100 MHz for standard read operations, while the AT25DF041A supports up to 70 MHz. Exact maximum frequencies depend on the operating voltage and read command used, so the datasheet AC characteristics should be consulted for the specific operating conditions.
What are the operating voltage and temperature ranges for these parts?
Both devices operate from a single 2.7 V to 3.6 V supply. The AT25DF081A-SSH-T is specified for the industrial temperature range of -40 °C to +85 °C. The AT25DF041A-SHF-B carries the "HF" ordering suffix, which denotes a specific temperature/operating grade; designers should confirm the exact rated temperature range from the AT25DF041A datasheet ordering information before use in a given application.
Can the AT25DF041A-SHF-B be used as a drop-in replacement for the AT25DF081A-SSH-T?
No, not as a direct drop-in replacement. Although both are 8-lead SOIC SPI flash devices with compatible pinouts, the AT25DF041A has half the density (4 Mbit vs 8 Mbit) of the AT25DF081A. Firmware, memory maps, and any density-dependent commands or addressing must be validated. A drop-in replacement is only possible if the application's firmware and memory requirements are compatible with the smaller 4-Mbit density.
What are the typical endurance and data retention specifications?
The AT25DF series flash memories are typically rated for 100,000 program/erase cycles per sector and 20 years of data retention at 85 °C. These are typical datasheet values for the family; designers should confirm the exact endurance and retention figures in the specific device datasheet for the AT25DF081A and AT25DF041A before finalizing reliability calculations.
What package and ordering code information should be verified before design-in?
The "-SSH-T" suffix on the AT25DF081A indicates an 8-lead SOIC package in tape-and-reel packaging, and the "-SHF-B" suffix on the AT25DF041A indicates an 8-lead SOIC package in bulk/tube packaging with a specific temperature grade. Designers should verify the exact package dimensions, moisture sensitivity level, and packaging quantity from the manufacturer's ordering information to ensure compatibility with assembly and inventory requirements.