Tantalum Capacitor Characteristics And Applications

As a class of electrolytic capacitors, the tantalum capacitor is widely used in communications, aerospace and military industries, submarine cables, advanced electronic devices, civil appliances, televisions, and many other aspects.

 

 

Tantalum capacitors are made of metal tantalum (Ta) as the anode material. According to their different anode structures, tantalum capacitors can be divided into foil tantalum capacitors and tantalum powder-sintered tantalum capacitors.

 

And the tantalum powder sintered tantalum capacitors can be divided into tantalum capacitors with solid electrolytes and tantalum capacitors with non-solid electrolytes according to their different working electrolyte. Among them, the market demand for solid tantalum electrolytic capacitors is large, such as UF Capacitors CA42 type.

 

 

 

 

Compared with aluminum electrolytic capacitors, tantalum electrolytic capacitors have the following advantages:

 

1. Small In Size

Because tantalum capacitors use tantalum powder with very fine particles, and the dielectric constant of the tantalum oxide film is 17 higher than that of the aluminum oxide film, the tantalum capacitor has a large capacitance per unit volume.

 

2. Wide Operating Temperature Range

Generally, tantalum electrolytic capacitors can work normally at a temperature of -50°C to 100°C. Although aluminum electrolytic capacitors can also work in this range, the electrical performance is far inferior to tantalum electrolytic capacitors.

 

3. Long Service Life, High Insulation Resistance, Low Leakage Current

The tantalum oxide film medium in the tantalum electrolytic capacitor is not only resistant to corrosion but also can maintain good performance for a long time.

 

4. Good Impedance Frequency Characteristics

For capacitors with poor frequency characteristics, the capacitance decreases significantly when the operating frequency is high, and the loss also increases sharply. But solid tantalum electrolytic capacitors can work above 50kHz. With the increase in frequency, tantalum capacitors will also show a decrease in capacity, but the decrease is relatively small.

Data show that when working at 10kHz, the capacity of tantalum capacitors drops by less than 20%, while the capacity of aluminum electrolytic capacitors drops by as much as 40%.

 

5. High Reliability

Tantalum oxide film has stable chemical properties, and because Ta2O5, the tantalum anode substrate, can withstand strong acids and bases. Therefore, it can use solid electrolytes or liquid electrolytes with low acid resistivity, which makes the loss of tantalum electrolytic capacitors less than that of aluminum electrolytic capacitors, and the temperature stability is good.

 

 

 

 

Following cross reference chart from UF capacitors FYI

 

	Description	UF Capacitors Equivalent Series Code	Kemet	AVX
	Polymer Tantalum Capacitors	CA55 Series CA55T107M0006000BR070 CA55T106M0035000CR200 .......	T520B107M006ATE070 T520A107M006ATE045 T521X337M016ATE025 T521X227M016ATE035	TCJC106M035R0200 TCJD226M035R0100 TCJA106M020R0150
	Tantalum Chip Capacitors, General Purpose, A,B,C,D,E Case	CA45 Series CA45T155K0050000CR CA45T226K0016000BR	T489C155K050ATE2K5 T491C106M016AT4100 T490B157MO06ATE500	TAJB226K016RNJ TLJA476M010R0600
	Low ESR Chip Tantalum Capacitors, A,B,C,D,E Case	CA45U Series CA45UT475K0016000CR201 CA45UT106M0035000DR120	T494T475K016AT T494T106K006AH T495X227KO10AHE045 T495D106M035ATE120	TPSA106K010R0900 TPSA475K010R1400 F931V226MNC
	Radial Epoxy Dipped Tantalum Capacitor	CA42 Series CA42T105K00350025B000 CA42T226K00350050B000	T350B474M050AS7301 T350C106M010AT7303	TAP226K035CCS