CAPACITOR

A polar electrolytic capacitor whose anode electrode (+) is made of an aluminum foil with an etched surface, which is anodized and surrounded by a thin aluminum oxide insulating layer, which acts as the capacitor's dielectric. The alumina is coated with a non-solid electrolyte, which serves as the cathode (-) of the capacitor. In addition, there is a layer of aluminum foil called "cathode aluminum foil". The cathode foil is in contact with the electrolyte and connected to the negative terminal of the capacitor

Step 1: Structure

Polar aluminum electrolytic capacitors are made of aluminum foil (positive electrode) with oxide film and backing paper impregnated with electrolyte, and cathode (negative electrode) foils are stacked together. Appearance packaging is tubular and vertical. The aluminum housing has a blue or black plastic sleeve.

Step 2: Advantages

The capacity range is large, generally 1~10 000 μf, and the rated working voltage range is 6.3V ~ 450V.

3. Weakness

The medium loss is large, the capacity error is large (maximum allowable deviation +100%,-20%), the high temperature resistance is poor, and the storage time is long and easy to fail.

Step 4: Use

In DC power supply circuits or medium and low frequency circuits, it usually plays the role of filtering, decoupling, signal coupling, time constant setting and DC isolation. Note: Cannot be used in AC power circuits. When a filter capacitor is used in a DC power supply, the polarity cannot be reversed.