Kemet Vishay Replacements for Tantalum Capacitors

The full name of a tantalum capacitor is tantalum electrolytic capacitor, which belongs to the category of electrolytic capacitors. Compared to aluminum electrolytic capacitors, tantalum capacitors are more expensive. Historically, the first tantalum capacitor was developed in 1956 by Bell Labs in the United States. It achieves a high capacitance in a compact size while maintaining excellent performance.

Tantalum capacitors offer high capacitance density, low ESR (Equivalent Series Resistance), high temperature stability, low leakage current, and long lifespan, making them widely used in electronic product design. Structurally, a tantalum capacitor uses a tantalum metal sheet as the electrode, with tantalum oxide (Ta₂O₅) as the dielectric. A very thin dielectric layer exists between the tantalum oxide film and the tantalum metal sheet. The entire structure is encapsulated in a plastic or metal case to ensure structural stability and protect it from environmental influences.

Package Types

Tantalum capacitors are mainly available in two package forms:

1. Surface-Mount Tantalum Capacitors (SMD)
2. Leaded Tantalum Capacitors

They are polarized components:

• For SMD tantalum capacitors, the marked end indicates the positive terminal (opposite to some aluminum electrolytic capacitors, where the marked end is the negative terminal).
• For leaded tantalum capacitors, the longer lead is the positive terminal.

 Warning: Tantalum capacitors must not be reverse-biased, as this can cause overheating, burning, or even explosion.

Key Electrical Characteristics

1. Capacitance (C)

• Capacitance decreases with increasing frequency.
• It slightly increases with temperature, but due to the excellent temperature coefficient of tantalum capacitors (using solid MnO₂ electrolyte), the capacitance remains relatively stable.

2. Rated Voltage (V_R)

• The datasheet typically specifies the maximum DC voltage at a certain temperature (usually below 85°C).
• When the temperature exceeds 85°C, the rated voltage derates. For example, at 125°C, the rated voltage may drop to two-thirds of its original value.

3. Leakage Current (DCL)

• The DCL (DC Leakage Current) value is a critical parameter for tantalum capacitor performance.
• The decay rate of leakage current and its variation at high temperatures significantly impact reliability.

4. Dissipation Factor (DF)

• DF represents the power loss in the capacitor when an AC signal is applied.
• A higher DF may shorten the capacitor’s lifespan, so lower values are preferred.
• The formula is: DF = R_S / X_C (where R_S is the equivalent series resistance, and X_C is the capacitive reactance).
• DF generally increases with frequency.

5. Insulation Resistance (IR)

• IR is a specified value measured at room temperature.
• The capacitor is charged to its rated voltage for 1 or 2 minutes, and the IR is calculated as:
  IR = Voltage / Average Leakage Current (after 1 or 2 minutes).

6. Equivalent Series Resistance (ESR)

• ESR affects power ripple and PDN (Power Delivery Network) simulations.
• MLCCs (Multilayer Ceramic Capacitors) typically have very low ESR (in the milliohm range), while tantalum capacitors have higher ESR (usually in the ohm range).

UF Capacitors is a specialized manufacturer and supplier of high-quality tantalum capacitors. We offer competitive alternatives to leading international brands, with better lead times, more cost-effective pricing, and superior sales support. Our products have earned consistent praise from global customers for their reliability and performance.

Why Choose UF Capacitors?

Premium Quality – Our tantalum capacitors meet stringent industry standards, ensuring high stability, low ESR, and long lifespan, we can supply alternative tantalum capacitors of Kemet, AVX, Vishay.
Faster Delivery – Optimized production and logistics enable shorter lead times compared to competitors.
 Cost-Effective Pricing – We provide high-performance tantalum capacitors at more competitive rates without compromising quality.
Exceptional Customer Support – Our dedicated sales and technical teams ensure prompt and professional service.

Global Recognition

Our products have been widely adopted in consumer electronics, automotive, medical, and industrial applications, earning trust from clients worldwide.

UF Capacitors Tantalum Capacitor Cross Reference
Photo	Description	UF Capacitors Series Code	Kemet	AVX	Vishay
	Polymer Tantalum Capacitors	CA55 Series	T520 Series T521 Series	TCJ Series	T55 Series
	Tantalum Chip Capacitors, General Purpose, A,B,C,D,E Case	CA45 Series	T491 Series T490 Series T489 Series	TAJ Series F913 Series TLJ Series	293D Series
	Low ESR Chip Tantalum Capacitors, A,B,C,D,E Case	CA45U Series	T494 Series T495 Series	TPS Series F93 Series	593D Series 594D Series TR3 Series
	Radial Epoxy Dipped Tantalum Capacitor	CA42 Series	T350-T390 Series	TAP Series	199D Series 489D Series ETPW Series ETQW  Series

UF Capacitors – Better Performance. Better Service. Better Value

Contact us: carey@ufcapacitors.com