We use cookies to improve your online experience. By continuing browsing this website, we assume you agree our use of cookies.
Company News

Analysis of Temperature Characteristics and Service Life of SMD Capacitors

Views : 22
Update time : 2025-01-21 15:31:32
SMD capacitors, as an indispensable component of modern electronic components, are widely used in various electronic products, such as communication equipment, consumer electronics, automotive electronics, and industrial control systems. The stability of their performance directly affects the operational reliability of the entire circuit. Temperature characteristics and service life are two important factors that affect the performance of SMD capacitors. This article will conduct an in-depth exploration of the temperature characteristics of SMD capacitors, their impact on service life, and how to extend their service life through rational selection and application, thereby providing scientific guidance for relevant practitioners.
 

I. Overview of Temperature Characteristics of SMD Capacitors

1.1 Impact of Temperature on Capacitance Value
The temperature characteristics of SMD capacitors refer to the changes in capacitance value under different temperature environments. The capacitance value changes with the increase or decrease of temperature, and this change is usually determined by the characteristics of the internal materials of the capacitor. Specifically, different types of capacitors such as ceramic capacitors, aluminum electrolytic capacitors, and tantalum capacitors exhibit different capacitance value change characteristics at different temperatures.

Ceramic Capacitors: The temperature characteristics of ceramic capacitors are usually characterized by their temperature coefficient (TC). Common ceramic capacitors have different temperature coefficient categories such as NPO (C0G), X7R, and Y5V. NPO capacitors have a small temperature coefficient, and their capacitance changes very slightly, usually between 0 to +70°C, with a change of less than ±1%. While low-cost ceramic capacitors like Y5V capacitors, their capacitance values will decrease significantly with the increase of temperature, and the change range may reach -82%.

Aluminum Electrolytic Capacitors: Aluminum electrolytic capacitors have a relatively large temperature coefficient. Usually, with the increase in temperature, their capacitance values will also change, and the electrolyte in a high-temperature environment may volatilize, resulting in a decline in capacitor performance.

Tantalum Capacitors: Tantalum capacitors have good temperature characteristics, and temperature changes have relatively little impact on them. Especially in normal temperature and lower temperature environments, their capacitance values change relatively stably.

1.2 Impact of Temperature on Other Properties of Capacitors
In addition to the capacitance value itself, temperature will also affect other properties of capacitors, such as leakage current and internal resistance. The increase in temperature will accelerate the chemical reactions inside the capacitor, increasing the leakage current and internal resistance. Especially in a high-temperature environment, the leakage current of electrolytic capacitors and tantalum capacitors may increase significantly, leading to capacitor failure or shortened service life.

Leakage Current: Leakage current refers to the current generated under non-ideal conditions when a voltage is applied to the capacitor. With the increase in temperature, the leakage current of the capacitor usually increases, especially in electrolytic capacitors and tantalum capacitors. High temperature will accelerate the evaporation of the electrolyte, resulting in a further increase in leakage current.

Internal Resistance: The internal resistance of the capacitor usually increases with the increase in temperature, mainly because the resistivity of the material changes with temperature, increasing the internal energy loss of the capacitor. Excessive internal resistance will affect the performance of the capacitor and even lead to capacitor failure.

 

II. Analysis of Service Life of SMD Capacitors

2.1 Relationship between Service Life and Temperature
The service life of capacitors is usually determined by internal chemical and physical changes. The high-temperature environment accelerates the aging process inside the capacitor and shortens its service life. Therefore, temperature is a key factor affecting the service life of capacitors.

Ceramic Capacitors: The service life of ceramic capacitors is less affected by temperature, but in a high-temperature environment, the fluctuation of capacitance value may affect its long-term stability. Although the failure rate of ceramic capacitors is relatively low, in an extremely high-temperature environment, cracks or damage may also occur, thereby affecting its performance.

Aluminum Electrolytic Capacitors: The service life of aluminum electrolytic capacitors is very sensitive to temperature changes. In a high-temperature environment, the volatilization of the electrolyte and the corrosion of the electrodes intensify, resulting in a gradual decrease in the capacitance of the capacitor. Generally speaking, for every 10°C increase in temperature, the service life of aluminum electrolytic capacitors will be halved. Therefore, selecting an appropriate working temperature range is crucial for the long life of aluminum electrolytic capacitors.

Tantalum Capacitors: Tantalum capacitors have a relatively long service life, but in a high-temperature environment, they will also face problems such as increased leakage current and capacitance value fluctuations. Compared with aluminum electrolytic capacitors, the temperature characteristics of tantalum capacitors are relatively stable, but they may still be damaged at excessively high temperatures.

2.2 Measurement and Prediction of Service Life
The service life of capacitors can be predicted through accelerated aging tests. Commonly used aging tests include high-temperature storage tests and load tests. Through these tests, the service life of capacitors in practical applications can be predicted. Common life indicators include:

High-Temperature Life: Refers to the durability of capacitors in a high-temperature environment. For aluminum electrolytic capacitors, the commonly used test temperature is 105°C, and the test time is usually 1000 hours to 3000 hours.

Rated Life: Refers to the service life of capacitors underrated working conditions. Generally, the rated life of aluminum electrolytic capacitors is about 2000 to 5000 hours.

Failure Rate: Failure rate is the probability of capacitor failure due to temperature, load, and other reasons during use. The failure rate of SMD capacitors is usually relatively low at lower operating temperatures, but with the increase in temperature, the failure rate shows exponential growth.

 

III. How to Extend the Service Life of SMD Capacitors

3.1 Selecting an Appropriate Temperature Range
To extend the service life of SMD capacitors, selecting an appropriate temperature range is crucial. Most capacitors have a maximum operating temperature range, and exceeding this range will accelerate the aging of the capacitor. Therefore, when designing the circuit, the operating environment temperature must be reasonably selected according to the temperature characteristics of the capacitor.

Ceramic Capacitors: For most applications, the NPO (C0G) series of ceramic capacitors can provide relatively stable temperature characteristics and are suitable for environments with large temperature changes.

Aluminum Electrolytic Capacitors: When using aluminum electrolytic capacitors in a high-temperature environment, it is recommended to select products with a higher temperature resistance level (such as 125°C) and try to avoid long-term operation at high temperatures.

Tantalum Capacitors: Tantalum capacitors are suitable for applications with low sensitivity to temperature changes, but they still need to be used with caution at excessively high temperatures.

3.2 Appropriately Reducing the Operating Voltage
The operating voltage also has a certain impact on the life of the capacitor. Long-term operation at the rated voltage will accelerate the aging process inside the capacitor. To extend the service life of the capacitor, it is recommended to reduce the operating voltage of the capacitor as much as possible during design to reduce the electric field strength of the capacitor.

3.3 Providing Good Heat Dissipation
In a high-temperature environment, the heat dissipation capacity of the capacitor is crucial. By optimizing the circuit design and the external heat dissipation system, the operating temperature of the capacitor can be effectively reduced, thereby extending its service life.

3.4 Regular Inspection and Maintenance
For capacitors that work in a high-temperature environment for a long time, regular inspection and maintenance can help detect potential problems in time and prevent capacitor failure. By detecting indicators such as leakage current and internal resistance, the health status of the capacitor can be effectively evaluated.

 

IV. Conclusion

There is a close relationship between the temperature characteristics and service life of SMD capacitors. Different types of capacitors exhibit different electrical characteristics under temperature changes, and the increase in temperature will accelerate the aging process of capacitors and shorten their service life. To extend the service life of capacitors, engineers need to reasonably select the operating temperature and operating voltage of capacitors during design and provide appropriate heat dissipation measures. At the same time, regular inspection and maintenance of capacitors are also effective means to ensure their long life.
 

Hot-selling products of SIC

TMS320F28069MPZT TMUX1308QPWRQ1         TPS544C25RVFT              TPS2001DDBVR         TPS3711DDCT       TPS22953DQCR                       
TPS22958NDCNR TPS22966DPUT TPS22975NDSCR TPS22976DPUT TPS23755RIJT TPS54618CQRTERQ1

Tips on selecting capacitors are from SIC Electronics Limited. If you are interested in the product or need product parameters, you can contact us online at any time or send us an email: [email protected].
Related News
Read More >>
STM32L051K6T6 vs STM32C031C6T6 STM32L051K6T6 vs STM32C031C6T6
Feb .17.2025
This article offers valuable insights into the specifications and functions of the STM32L051K6T6 and STM32C031C6T6 microcontrollers through a detailed comparison.
STM32L051K6T6 vs STM32C031K6T6 STM32L051K6T6 vs STM32C031K6T6
Feb .17.2025
This article offers valuable insights into the specifications and functions of the STM32L051K6T6 and STM32C031K6T6 microcontrollers through a detailed comparison.
STM32F103VCT6TR vs STM32F030K6T6 STM32F103VCT6TR vs STM32F030K6T6
Feb .15.2025
This article offers valuable insights into the specifications and functions of the STM32F103VCT6TR and STM32F030K6T6 microcontrollers through a detailed comparison.
STM32F103VCT6TR vs STM32F031C6T6 STM32F103VCT6TR vs STM32F031C6T6
Feb .15.2025
This article offers valuable insights into the specifications and functions of the STM32F103VCT6TR and STM32F031C6T6 microcontrollers through a detailed comparison.