Capacitors are the most common electronic components in electronic equipment. Of course, they are even more common on our motherboards and graphics cards. Solid capacitors are already standard. Even some high-end desktop power supplies are beginning to be equipped with solid capacitors. However, more than ten years ago, electrolytic capacitors were still the main force on motherboards, and solid-state capacitors were only equipped in the CPU power supply section of some high-end motherboards and were promoted as highlights by manufacturers.
The principle of a capacitor is actually two conductors close to each other with a layer of non-conductive dielectric sandwiched between them. When a voltage is applied between the two plates of the capacitor, the capacitor will store charge.
At present, capacitors play an important role in tuning, bypass, coupling, filtering and other circuits. Depending on the dielectric material of the interlayer, there are electrolytic capacitors, solid capacitors, tantalum capacitors, mica capacitors, ceramic capacitors and air capacitors.
The so-called electrolytic capacitor uses liquid electrolyte as the dielectric material. The advantage of this type of capacitor is low production cost, but the electrolyte is more active at high temperatures and has a low boiling point.
If the working temperature is too high, it will expand due to heat and generate pressure inside the capacitor. If the boiling point is exceeded, the capacitor shell may break through and explode.Therefore, in addition to the capacity and withstand voltage value, the outer skin of the electrolytic capacitor is also marked with a temperature resistance value, which is usually tens of degrees Celsius or more than one hundred degrees Celsius.
In addition, since the electrolyte will gradually be consumed over time, this will cause the capacitor capacity to decrease, which may bring hidden dangers to other parts of the circuit. For example, some old motherboards may suffer from high load operation in the later period. If you restart for no reason, you may not be able to boot in the future. After checking, the electrolytic capacitor in the CPU power supply part is often the culprit.
In order to make motherboards and graphics cards more stable and last longer, solid capacitors are becoming increasingly popular. Solid capacitors, as the name suggests, use polymer solid materials as dielectric materials. Solid materials naturally do not explode due to thermal expansion, and can withstand temperatures as high as 260°C or more, greatly increasing stability and service life. .
It also has superior characteristics such as environmental protection, low impedance, high and low temperature stability, high ripple resistance and high reliability. It is suitable for low voltage and high current applications, so it has been widely used in computer board products in recent years, and electrolytic capacitors are often used in The less loaded areas on the motherboard, such as the network card and sound card.
Of course, the distinction between electrolytic capacitors and solid-state capacitors is also very simple. Electrolytic capacitors usually have colorful plastic skins with various parameters marked on them, while solid-state capacitors often have exposed aluminum shells without plastic skins.
However, some electrolytic capacitors also have directly exposed aluminum shells without plastic skins, so the most direct way to judge is that the top of the electrolytic capacitor shell is designed with cross or K-shaped grooves or protrusions. This is mainly to allow the high-temperature and high-pressure electrolyte to pass through. The shell can be broken out from here to avoid capacitor explosion to the greatest extent.
There is no slot design on the top of the solid capacitor. The entire shell is a whole. Look carefully at the top of the capacitor in the picture below. This is an aluminum shell electrolytic capacitor.
Nowadays, many motherboards regard all-solid capacitors as a selling point, but the performance of motherboards depends on many aspects besides materials, including PCB circuit design, BIOS, etc. This is also the key to the “Yusanjia” brand becoming “Yusanjia”.