SSD and HDD memory

We chose this invention because today we use much computers and laptops and these memory systems enable saving, storing and reading information. Physics is involved to this because there is magnetism, electromagnetism, mechanical reader, data and electrical signals. There are multiple kinds of storage Hard Disk Drives (HDD) and Solid State Drive (SDD). HDD is slower than SSD memory and it won’t work so many years as the SSD does, but SSD's capacity is lower than HDD's. SSD is used be a storage location for example to Windows operating system. Explanations to the abbreviations are at the end of the article.

HDD

Hard Disk Drive (HDD) is based on moving discs (platters) which are coated with magnetic material. HDD's other the most important parts are Actuator and the Slider and magnetic Head. The Actuator includes two strong magnets and voice coil of actuator's arm which makes the actuator's arm and head moving that the data can be read from the discs wrote to them. The voice coil works using electromagnetic attraction and repulsion. The data is read and saved by the mechanical reader "Head".

The most popular hard disks are usually about 500 GB but generally some laptops could have only 160-320 GB Hard disks.

Picture1. HDD's parts

Pictures The Head & The data reading

The data is stored digitally as tiny magnetized bits on the disk. The head moves above the magnetically coated plate and as it passes the sections of the platter it measures changes of the magnetic poles. A magnetic orientation in one direction on the disk could represent a "1" and an orientation in the opposite direction could represent a "0".

Picture2. How data is stored in HDD

SSD

Solid State Drives are electronic working of silicon memory chips and it uses NAND based flash memory. There are any moving parts like spinning platters so they are very fast and shock resistant. Inside the SSD are five main parts. These are controller, NAND flash memory (the black boxes on the picture's circuit board, cells) , SATA interface, SSD PCB and card (circuit board). The most of the Solid State Drives' capacity are 30/32, 60/64 or 120/128 GB.

Picture3. SSD's parts

NAND Flash Technology of SSD

There are mainly two different NAND Flash types used today, Single-Level Cell (SLC) and Multi-Level Cell (MLC). NAND Flash stores data in a large array of cells. Every cell can store data: 1 bit per cell for SLC NAND and 2 bits for cell for MLC. SLC NAND stores a "0" or "1" in each cell and MLC NAND stores "00", "01", "10" or "11" in each cells. SLC and MLC differences are levels of performance and endurance characteristics at different prices. SLC is higher performing and more expensive than MLC.

Picture4. SDD cards

How is info read from SSD?

The information is travelling from the SSD to the computer through a standard SATA connection. Inside the SSD the controller is an embedded processor that bridges flash memory components to the host (such as a computer).

The controller executes codes provided by the SSD's firmware (a mini operating system) to full-fill the data requests from the host. The information is stored and read with zeros and ones in cells. The memory cells store voltage and (in SLC cells) can be either an on (1) or off (0), which allows them to store data in binary form.

SATA = is a computer bus interface which connects host bus adapters to mass storage devices such as hard disk drives and optical drives.

SSD = Solid State Drive

HDD = Hard Disk Drive

SLC = Single-level cell

MLC = Multi-level cell

How the energy flows & transforms in your team's invention ?

Se there is two magnets in the actuator and voice coil. The current is supplied from two directions alternately which affects electromagnetism because the coil is between the two magnets N pole and S pole. The electromagnetism affects then that the actuator's arm moves. So current's work changes to kinecic energy. Then the kinetic energy causes induction to the head (the head has coil and ferromagnetic core) because the head moves above the magnetically coated plate and as it passes the sections of the platter it measures changes of the magnetic poles. So as in the Faraday's law the current is induced to the current loop when the magnetic flux through to the loop changes. Also some the kinetic energy can affect warming so the efficiency isn't perfect (as it never is).

How the energy interacts with matter in your team's invention ?

The different energies and forces affects the parts (matters') motion and probably a bit warming. The forces and energies bases on current (electrons' motion) and the current's affected magnetism.