Views: 2 Author: Site Editor Publish Time: 2018-03-17 Origin: Site
Electrolytic capacitors can not cover the world:
Aluminum electrolytic capacitors can obtain high capacitance, which seems to replace other capacitors. But that's not the case. Electrolytic capacitors don't cover the world.
Electrolytic capacitors are polar and not suitable for working under bipolar voltages. Except for short-time motor starting capacitors and acoustical AC electrolytic capacitors, electrolytic capacitors can only work at DC voltage. At least the capacitor terminal voltage cannot be reversed.
Because of the negative electrolyte of aluminum electrolytic capacitor, its esr value is much higher than that of thin film capacitor, ceramic capacitor and hollow capacitor under the same capacitance. The loss factor is much higher than that of thin film capacitor, ceramic capacitor and hollow capacitor. The esr and loss factor of tantalum electrolytic capacitors with spongy anode are much higher than those of other dielectric capacitors, although they are lower than those of aluminum electrolytic capacitors.
The corrosion effect of chloride ions in electrolyte on insulating dielectric film (alumina) makes the leakage current of aluminum electrolytic capacitor much higher than that of thin film capacitor ceramic capacitor hollow capacitor and so on.
The capacitance of electrolytic capacitors varies with the frequency and other factors, which makes the electrolytic capacitors unsuitable for applications where the capacitance stability is required. Due to high esr and poor heat dissipation capacity of capacitors, the current resistance of electrolytic capacitors is poor.
Because of the above factors, the electrolytic capacitor is the most suitable for AC rectifier filter, even the power bypass is not suitable. Other applications require dielectric capacitors such as thin film capacitors, ceramic capacitors, etc.