Application of CS SD NAND in Smart Wearable Watches and Bracelets
Recently, the domestic market for smart wearable watches and bracelets has become increasingly complex. However, functionally, they can be broadly classified into the following categories: smart watches for business professionals; location and medical emergency watches for children, the elderly, and other special groups; and fitness wristbands and music sports watches (featuring heart rate monitoring, step counting, blood oxygen measurement, and music playback).
With the increase in functionality, the storage capacity requirements for smartwatches are growing significantly. These requirements include storing audio music, videos, GUI interfaces, user data, and other information. For example, an MP3 file is roughly 3-5MB in size; storing about 20 songs would require approximately 100MB of space, not including space needed for the system and GUI interface. Traditional NOR Flash is therefore insufficient for these needs. Additionally, smartwatches have high integration levels and impose very stringent size requirements on components.
How to Choose a Storage Solution for Smart Wearables:
Option 1: Using TF Cards as External Storage
However, there are several drawbacks:
a) Size: The card and its slot require 13*15mm of space, which is too large for the limited space on a smartwatch.
b) Structural Issue: The TF card slot is a structural component, and the TF card can easily fall out during use.
c) Manufacturing: TF cards cannot be machine-mounted and must be assembled manually. This leads to low production yields and potential defects.
d) Waterproofing: The large slot opening makes it challenging to create a waterproof product.
e) Consistency: Especially for small-capacity TF cards, consistency is difficult to guarantee, resulting in quality variations between batches.
Option 2: Using eMMC for Storage
This is a common practice among international brands like Samsung and Huawei. For example, the Huawei GT2 uses a Toshiba eMMC, which has a size of 11.5*13mm.
Challenges of Using eMMC in Smartwatches for Domestic Customers:
A) Space Constraints: Without support from major component manufacturers or having an experienced hardware team, it’s challenging to fit an 11.5*13mm eMMC chip on a very small smartwatch PCB.
B) Overcapacity: Many customers only need 128MB or 512MB of storage. However, eMMCs commonly start at 8GB, making the high cost of eMMC a significant challenge for manufacturers without brand premiums.
C) Soldering Issues: Smartwatch PCBs are already very crowded. Adding a large 153-ball eMMC chip increases pressure on both the assembly factory and maintenance personnel.
Addressing the Shortcomings of Previous Solutions,CS SD NAND provides the following advantages:
1) Compact Size: With a 6*8mm package, it occupies only 1/3 of the area of eMMC and 1/4 of a TF card.
2) Fewer Pins and Easy Soldering: The LGA-8 package is convenient for both machine and manual placement.
3) Appropriate Capacity: Available in 128MB, 512MB, and 4GB capacities, allowing customers to choose according to their needs and manage costs effectively.
4) Stable Performance: Utilizes the most stable SLC NAND Flash with an endurance of 5 to 10 million write cycles. In contrast, the mainstream NAND Flash in TF cards and eMMCs is TLC, which has an endurance of around 500 cycles.
5) Easy to Use: Compatible with SD protocol, allowing use with any CPU that supports SD interfaces without requiring additional drivers.
The CS SD NAND has a promising application prospect in smartwatches and wristbands and can help customers address many practical issues. Currently, Leilong offers matching test boards, test sockets, and free samples for SD NAND. Feel free to contact us for more information.
