Key Differences Between POLYMER Tantalum Capacitors and Ordinary Tantalum Capacitors

2025-08-03

In the field of electronic components, tantalum capacitors are widely used for their high capacitance density and stable performance. However, with the development of material technology, tantalum capacitors using conductive polymers as electrolytes (POLYMER Tantalum Capacitors) have formed significant differences from traditional ordinary tantalum capacitors.

Taking AVX's TCM series conductive polymer tantalum capacitors as an example, their differences from ordinary tantalum capacitors are mainly reflected in material properties, performance, reliability, and application scenarios.

I. Electrolyte Material: A Fundamental Leap from MnO₂ to Conductive Polymers

Ordinary tantalum capacitors typically use manganese dioxide (MnO₂) as the core electrolyte, while polymer tantalum capacitors use conductive polymers as the electrolyte—which is the most fundamental difference between the two.

AVX's TCM series is clearly labeled as "Conductive Polymer Solid Electrolytic Chip Multianode Capacitors," with conductive polymers as the cathode material, whereas traditional tantalum capacitors (such as AVX's T series) use MnO₂ as the electrolyte. This material difference directly leads to differentiation in their electrical performance and stability: conductive polymers have higher conductivity, while MnO₂ has relatively limited conductivity, which is the core root of subsequent performance differences.

As a conductive polymer tantalum capacitor, Hongda Capacitors' CA55 series shares the same core material as the TCM series, both using conductive polymer electrodes, which provides it with the basic characteristics to replace the TCM series.

II. Performance: Comprehensive Improvement in High Frequency, Low Resistance, and Efficiency

1. Extremely Low ESR (Equivalent Series Resistance)

The high conductivity of conductive polymers enables polymer tantalum capacitors to have significantly lower ESR than ordinary tantalum capacitors. The maximum ESR of AVX's TCM series ranges from 6 to 100mΩ (@100kHz). For example, the TCME108M004#0006E model with 1000μF/4V specification has an ESR of only 6mΩ. In contrast, ordinary tantalum capacitors, due to the resistance characteristics of MnO₂ electrolytes, usually have higher ESR, especially in high-frequency scenarios, the difference is more obvious.

Hongda Capacitors' CA55 series also features "Lower ESR," with an ESR range close to that of the TCM series. For instance, some models can have an ESR as low as 25mΩ (@100kHz), which can meet the low resistance requirements of high-frequency circuits, making it highly adaptable when replacing the TCM series.

2. Better High-Frequency Capacitance Retention

In high-frequency circuits, the capacitance of ordinary tantalum capacitors tends to attenuation with increasing frequency. In contrast, conductive polymer tantalum capacitors, relying on their material properties, can maintain more stable capacitance output at high frequencies. AVX's TCM series explicitly lists "High Frequency Capacitance Retention" as a core feature, making it perform better in scenarios such as high-frequency DC/DC conversion.

The CA55 series also emphasizes "improved capacitance retention at high frequencies," which is highly matched with the TCM series in high-frequency performance and can adapt to similar high-frequency application scenarios, such as DC/DC converters and radio frequency modules in communication equipment.

3. Stronger Surge Resistance

Ordinary tantalum capacitors have poor tolerance to instantaneous surge currents, while conductive polymer tantalum capacitors, through structural optimization and material properties, have stronger surge resistance. AVX's TCM series has passed "100% Surge Current Tested," enabling it to remain stable under sudden current impacts and reduce the risk of failure.

The CA55 series features "High ripple handling," indicating its reliability in coping with ripple currents and surge impacts, and like the TCM series, can adapt to current fluctuations in high-power scenarios.

III. Reliability and Process Adaptability: Stable Performance in Harsher Environments

1. Higher Reflow Soldering Tolerance

In the electronic assembly process, the high-temperature environment of reflow soldering is an important test for capacitor stability. Conductive polymer tantalum capacitors have better heat resistance. AVX's TCM series supports "3x reflow cycles according to J-STD-020," while ordinary tantalum capacitors, limited by the thermal stability of MnO₂, usually have fewer reflow cycles and weaker process adaptability.

Hongda Capacitors' CA55 series also performs well in reflow soldering tolerance, capable of withstanding "3x260°C peak for max. 10s reflow," which is comparable to the process compatibility of the TCM series and meets the stringent requirements of automated welding production lines.

2. More Outstanding Wide-Temperature and Environmental Stability

Although both can cover the operating temperature range of -55°C to +125°C (the TCM series is -55°C~+125°C, and the CA55 series is -55°C~+105°C), there are significant differences in parameter stability under extreme environments. According to AVX's reliability tests, in the 125°C endurance test, the ESR change of the TCM series does not exceed twice the initial value, and the capacitance change is controlled within ±20%; while ordinary tantalum capacitors, under high temperature or high humidity, usually have greater capacitance attenuation and ESR increase.

Although the upper limit of the operating temperature of the CA55 series is slightly lower, it shows excellent stability within its own specifications. Its leakage current (DCL) is controlled within 0.1CV, and there is no aging effect ("No aging effects"). The parameter drift during long-term use is smaller, and like the TCM series, it can meet the long-life requirements of industrial-grade equipment.

IV. Application Scenarios: Extension from General-Purpose to High-Frequency, High-Power Scenarios

Ordinary tantalum capacitors are suitable for medium and low-frequency scenarios with low requirements for ESR and high-frequency performance (such as power filtering in ordinary consumer electronics). Due to the above performance advantages, conductive polymer tantalum capacitors are more suitable for fields with high-frequency, high-power, and high-reliability requirements.

The typical applications of AVX's TCM series include "Telecommunication Routers" and "Base Stations with High Power DC/DCs." The application scenarios of the CA55 series highly overlap with those of the TCM series, covering DC/DC converters, communication base stations, smartphones, servers, microprocessor decoupling, etc. It performs particularly well in high ripple current and high-density circuits, making it an ideal alternative to the TCM series.

Click on the datasheet link to discover more information:

https://www.hongdacapacitors.com/res/Tantalum-Capacitors/ca55-polymer-chip-tantalum-capacitors.pdf

V. Environmental Protection and Compliance: More Flexible RoHS Adaptability

In terms of environmental protection compliance, conductive polymer tantalum capacitors are more likely to meet the RoHS requirements of modern electronic devices. AVX's TCM series is clearly labeled "RoHS COMPLIANT," and only the lead terminal (SnPb termination) option does not comply with RoHS. However, ordinary tantalum capacitors, due to process limitations, have relatively lower adaptability in environmental protection compliance.

Hongda Capacitors' CA55 series has also passed "RoHS and REACH compliance" certification, fully meeting mainstream global environmental standards, and is consistent with the TCM series in terms of green production and market access requirements.

Summary 

Through the innovation of electrolyte materials, conductive polymer tantalum capacitors have achieved comprehensive breakthroughs in ESR, high-frequency performance, surge resistance, and reliability, forming a complementary rather than replace relationship with ordinary tantalum capacitors. For applications in high-frequency, high-power, and harsh environments, polymer tantalum capacitors represented by AVX's TCM series and Hongda Capacitors' CA55 series are better choices. Among them, the CA55 series, with its performance parameters, process compatibility, and application adaptability highly matched with the TCM series, can be used as an alternative solution to meet the needs of various high-end electronic devices, while ordinary tantalum capacitors still have value in cost-sensitive or low-performance requirement scenarios.

Contact information: max@hongdacap.com.hk MP/whatsapp:+86 18188830464