This article explains very basic definition of What is a Capacitor ?, its main application and technologies.
Capacitor Definition
Capacitors are passive electrical components to store electric energy
A capacitor is made from electrical conductive electrodes that are separated by an insulator. The insulating layer is called a dielectric. Although all capacitors share the same basic principle components, the material choice, configurations and features can vary widely.
Overview of common capacitors symbols can be find in related article here.
A capacitor is able to store energy in an electrostatic field that is generated by a potential difference across the conducting electrodes. So when an electrode is subject to a voltage, one plate of the capacitor will collect positive charge while the other will be negatively charged. The ratio of this electric charge and the potential difference (voltage) is called the capacitance and it is expressed in farads. The leaking current through the dielectric is called the leakage current.
Applications – What is it good for ?
Capacitors are common elements in electrical circuits with number of applications and different requirements such as:
Here are further links with more insights about the capacitor circuit function and its selection guide:
- Bypass Capacitors: Providing clean power to devices by filtering noise and suppressing transients on supply lines.
- Decoupling Capacitors: Isolating sensitive components from noise by storing and releasing energy to maintain steady supply voltage during transients.
- DC-Blocking Capacitors: Preventing unwanted DC offsets from corrupting the AC or RF signals in these systems.
- DC Link Capacitors: acting as buffers that smooth power delivery and minimize ripples.
- Safety Capacitors: Protecting circuits and mitigate energy hazards in high-voltage systems.
- EMI Filters: suppressing electromagnetic noise generated by switched-mode power supplies, motor drives, and other electronics.
- Snubber Capacitors: Absorbing voltage spikes, limiting over-voltages.
- Resonant Capacitors: Leveraging this resonance to oscillate at specific frequencies, storing and releasing energy.
- Flying Capacitors: Transferring charges between different voltage potentials in multi-level power inverters.
- Bootstrap Capacitors: Enabling efficient high-side switching in half-bridge and full-bridge power converters.
Capacitor Technologies
There are wide capacitor technologies that differ in features, behaviour, range of electrical parameters covered. The most common capacitor technologies include:
The amazing fact about capacitors today is that they cover over 17 ranges ! of its main parameter – CAPACITANCE this hardly achieved by any other components technology.
