What Are the Main Components of an SSD Drive?

An SSD drive uses semiconductor memory to store data, making it a more efficient choice than traditional electromechanical storage media like hard disk drives (HDDs) for fast data access. SSDs also consume less power and are more resistant to physical shock, which can cause HDDs to fail over time.

The main components of a drive are the read and write heads, the stepper motor that moves them where they need to be, and the circuit board that controls the motors and other electronics in the drive. A mechanical frame creates a protective window that opens and closes as the head moves across the dual-sided disk media. The frame also contains levers that raise and lower the read/write heads to engage or disengage with the disk.

Most SSDs have a built-in flash controller that manages error correction, wear leveling, and data distribution to ensure all blocks are written as evenly as possible. This extends the lifespan of the SSD by minimizing the number of blocks that reach their maximum life, which reduces overall write arithmetic errors.

Manufacturers build their SSDs with different NAND (flash) chip technologies to offer a range of capacities. The most common is single-level cell (SLC) technology, followed by multi-level cell and triple-level cell (TLC). High-performance models use more advanced 3D V-NAND technologies for faster performance.

In addition to the NAND chip technologies, the other key factors that influence an SSD’s speed are the drive interface and the amount of dynamic RAM cache included. The former determines the maximum throughput and latency thresholds, while the latter specifies the amount of data that can be stored in memory.