SD NAND

   SD NAND IoT solution

[CS SD NAND] As everyone knows, the MCU is like a 'sparrow': small but fully equipped. It has a wide range of applications, from small devices like mobile phones and watches to large-scale aerospace equipment. Currently, several mainstream manufacturers in the market include STMicroelectronics (with the most classic being the STM32 series), TI, NXP, Microchip, Renesas, and others.

Regarding storage in MCUs, it used to be sufficient to use built-in EEPROM or external NOR Flash. However, with the rise of the Internet of Things (IoT), the application of MCUs has expanded significantly, and MCUs are gradually encountering the need for large-capacity storage to handle tasks like storing audio, images (GUI), video buffering, protocol stacks, etc.

At this point, traditional EEPROM and NOR Flash are no longer adequate. This is when MCUs may need to utilize NAND Flash. However, adopting large-capacity NAND Flash storage chips with MCUs presents new challenges:

1. Major MCU manufacturers like ST, TI, NXP, Microchip, Renesas, etc., generally do not provide official drivers for NAND Flash. Even in rare cases where some series do, many of the NAND Flash models listed as supported have already been discontinued.

2. If you attempt to write the driver yourself, you’ll face many frustrating issues: Using NAND Flash requires managing bad blocks and performing operations like EDC/ECC.

3. NAND Flash chips from different brands vary in parameters such as block size, page size, timing, etc., all of which require re-tuning the driver.

4. Even if the theoretical functionality is achieved, it’s well-known that MCUs, due to their low-power design, have compromised performance. Such complex driver programs can overwhelm the MCU, making it feel like a small horse pulling a large cart.

So, is there a simple, reliable NAND Flash product that meets the large-capacity storage needs of MCUs? The answer is yes. Let us proudly introduce the CS brand's SD NAND, also known as a surface-mount T card, surface-mount TF card, surface-mount SD card, surface-mount memory card, surface-mount flash card, surface-mount card, surface-mount USB drive, surface-mount UDP, and more.

The architecture of SD NAND is straightforward: it uses the longest-lasting and most stable NAND Flash (SLC NAND Flash) wafers, with an endurance of 50,000 to 100,000 write cycles. It has a built-in Flash controller and firmware specifically designed for NAND Flash management. Externally, it uses the most universal SD interface (which nearly all MCUs are equipped with).

CS SD NAND Architecture Diagram     

Package Size: The CS brand SD NAND features an LGA-8 package with dimensions of 6x8mm. The small size and compact pin layout not only save PCB space but also make soldering easier. Typically, MCU development boards are not overly complex (many are just two-layer boards), and this SD NAND package allows the PCB to remain simple and compact.

Density: Currently, 128MB and 512MB capacities are available, with a 4GB SD NAND version planned for the future. Customers can select the appropriate capacity based on their needs to reasonably reduce costs.

Built-in Firmware: The CS brand SD NAND includes built-in bad block management, wear leveling, dynamic and static EDC/ECC management algorithms. These features ensure more stable product quality and extend product lifespan. With its own Flash management algorithms, it alleviates the MCU from the burden of managing NAND Flash.

In summary, by using SD NAND, the MCU can operate more efficiently, as the SD NAND takes over the heavy load of NAND Flash management. When choosing a large-capacity NAND Flash for MCUs, SD NAND is the perfect match—like a "perfect pair."