What is the Difference Between Tantalum and Electrolytic Capacitor

The key difference between tantalum and electrolytic capacitor is that tantalum capacitors use a sintered pellet of high purity tantalum powder along with tantalum pentoxide as the dielectric component, whereas electrolytic capacitors are capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing.

Tantalum capacitors are a type of electrolytic capacitors that act as a passive component in electronic circuits. Electrolytic capacitors are polarized capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing.

CONTENTS

1. Overview and Key Difference
2. What is a Tantalum Capacitor  
3. What is an Electrolytic Capacitor
4. Tantalum vs Electrolytic Capacitor in Tabular Form
5. Summary – Tantalum vs Electrolytic Capacitor

What is a Tantalum Capacitor?

Tantalum capacitors are a type of electrolytic capacitors that act as a passive component of electronic circuits. This capacitor contains a pellet of porous tantalum metal as the anode of the capacitor. This anode is covered with an insulating oxide layer, which can form the dielectric. This component is surrounded by a liquid or a solid electrolyte that acts as the cathode. Tantalum capacitor is very thin and has a relatively high permittivity dielectric layer. We can distinguish it from other types of conventional and electrolytic capacitors since capacitance per volume is very high, and the weight is lower.

Tantalum is a chemical element having the chemical symbol Ta and atomic number 73. It is a rare, hard, blue-gray and lustrous transition metal. It is highly resistant to corrosion. This metal is widely used as a minor component in alloys due to it being a part of the refractory metal group.

We can observe that tantalum is a conflict mineral. These are more expensive than aluminum electrolytic capacitors, their competitor in the market. Moreover, these tantalum capacitors are highly polarized components, and the reverse voltage can destroy the capacitor.

In the basic principle of the tantalum capacitor, an oxide layer forms as a barrier around the tantalum anode after applying a positive voltage. The thickness of the oxide layer formed is proportional to the applied voltage. The oxide layer that forms here can act as a dielectric in the electrolytic capacitor.

The applications of tantalum capacitors include their use in the sample and hold circuits in order to achieve a long hold duration, as an alternative for aluminum electrolytic capacitors in solutions, in power supply filtering on computer motherboards and peripherals, etc.

What is an Electrolytic Capacitor?

Electrolytic capacitors are polarized capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing. The oxide layer that forms here can act as the dielectric of the capacitor. Usually, this oxide layer is covered in a solid, liquid, or gel electrolyte. These capacitors contain a very thin oxide layer and an enlarged anode surface. Therefore, these capacitors contain a much higher capacitance-voltage product per unit volume in comparison to that of ceramic capacitors and film capacitors. There are three major types of electrolytic capacitors: aluminum electrolytic capacitors, tantalum electrolytic capacitors, and niobium electrolytic capacitors.

Such types of capacitors are asymmetrical, and they must be operated with a high voltage on the anode. This voltage has to be higher than that of the cathode all the time. Therefore, the polarity is usually marked on the device housing.

What is the Difference Between Tantalum and Electrolytic Capacitor?

Tantalum capacitors are a type of electrolytic capacitors that acts as a passive component of electronic circuits. Electrolytic capacitors are polarized capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing. The key difference between tantalum and electrolytic capacitor is that tantalum capacitors use a sintered pellet of high purity tantalum powder along with tantalum pentoxide as the dielectric component, whereas electrolytic capacitors are capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing.

Below is a summary of the difference between tantalum and electrolytic capacitor in tabular form for side by side comparison.

Summary – Tantalum vs Electrolytic Capacitor

Electrolytic capacitors occur in three types as aluminum electrolytic capacitors, tantalum capacitors, and niobium electrolytic capacitors. The key difference between tantalum and electrolytic capacitor is that tantalum capacitors use a sintered pellet of high purity tantalum powder along with tantalum pentoxide as the dielectric component, whereas electrolytic capacitors are capacitors having an anode or a positive plate made of a metal that can form an oxide layer through anodizing.

Reference:

1. “Types of Capacitor and Their Construction.” Basic Electronics Tutorials, 10 July 2018.

Image Courtesy:

1. “Tantal-P1100196c” By Elcap (CC BY-SA 3.0) via Commons Wikimedia
2. “Electrolytic Capacitor-1” By Suyash Dwivedi – Own work (CC BY-SA 4.0) via Commons Wikimedia