Difference Between Solid State and Hard Drives
The complete lack of moving parts is the major difference here, hence the name 'solid state'. Unlike their counterpart; the hard drive, Solid State Drives (SSDs) do not use magnetic fields to retain data. As a result of the fact that they use an electrical current, as opposed to motors and magnets, for data storage, they are then able to access with a far lower consumption of power and, as a result with much less noise. In fact they can operate almost in silence.
Resistance to Impact
Another advantage of the Solid State system of operation is that unlike magnetic forces impact damage has very little effect. A major problem for a standard hard drive is an unhealthy knock of any kind. The robust nature of solid state drives mean that even after a punishing impact they are able to retain data and function normally. This feature makes them a very viable addition for any mobile computer. It is also a very useful aspect to have on a PC, especially if it is likely to move home during its lifetime.
How Does SSD Work?
In order to operate a solid state drives use pieces of silicone, semi conductors and a series of transistors to transfer the electrical current required by the system. As with everything within the computer system size is a crucial factor. For an SSD all of the parts are microscopic and can be operated through the transfer of a tiny amount of energy; just a few electrons will suffice. As with the majority of storage, the data in SSDs is converted into binary; a series of 1s and 0s used to signify elements of data. The 1s an 0s on and SSD are used to divide the electrical current; a 1 is represented by a transistor that allows the flow of electrical current, while the 0 is represented by a transistor which does not allow the flow of electrical current.
In a blank section of a drive, or on a completely blank drive, the binary is denoted by all 1s. Within this the transistors will allow a completely free flow of current. As data is recorded voltage is then applied to a single piece of silicone. This piece is known as a control gate. As part of the process electrons are transferred onto another piece of silicone which becomes known as the floating gate. When a floating gate becomes filled with electrons the current will not pass through and the drive then reads this as 0.
As data is written to or deleted from a solid state drive this information is converted by a program into a binary format. In the next part of the process this data is transmitted to the drive 19s writing center. Here it is converted in to electrical currents which are then used to realign the drive 19s transistors. In order to read the data the drive uses a read center where it transmits a current through a section which contains the data to be read and then returns this sequence in its binary format. This sequence is then processed through a program and presented as information for the user.
Benefits and Drawbacks
There are several benefits offered by SSDs but also there are a number of drawbacks in this format of system. The major advantage, as already highlighted is the mobility factor. The ability for the drive to operate while in motion and its resistance to data loss on impact have massive implications in terms of portable computing. The effects have this have already been felt in the laptop market with the development of the ultrabook and in terms of advancements with tablet PCs.
There are a few notable downsides to solid state technology and these are certainly worth a mention. One of the most considerable of these is that the transistors used have a limited life in terms of the number of times they can be written unto before they become saturated with data and unusable. The drives employ a sophisticated level of technology to prolong the lives called 18wear levelling 19 which is designed to prevent any section of the drive suffering from premature wear. Even with this technology SSDs are susceptible to failure when any individual section becomes unwritable. As such ordering replacement sections from manufacturers that are capable of delivering technology to the user is going to be a defining feature of viable solid state drive support for the user.
Credits for the article: Imogen Reed