AIC tech Inc. List of Products and Services

We would like to introduce a case where an aluminum electrolytic capacitor, which had been stored for a long time as a spare part, exhibited increased leakage current. Aluminum electrolytic capacitors have the property that their leakage current increases when stored for a long time without a DC bias and under no load, and this property becomes more pronounced at higher storage temperatures. This is believed to be due to the degradation of the dielectric oxide film at high temperatures, which reduces its insulation properties. When voltage is applied in this state, the leakage current increases. 【Countermeasures】 ■ Store capacitors at temperatures between +5°C and +35°C, with relative humidity below 75%. ■ Unless otherwise specified, our aluminum electrolytic capacitors can be stored without voltage under the above conditions for up to 3 years. ■ If within the storage period, capacitors can be used at rated voltage immediately after being taken out from storage. ■ For capacitors that will be mounted on a circuit board by soldering, to prevent issues during soldering, they should be mounted within 2 years. *For more details, please refer to the PDF document or feel free to contact us.

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We will introduce a case where a malfunction occurred during a low-temperature operation test of a DCDC converter, resulting in a decrease in output voltage. An aluminum electrolytic capacitor using electrolyte was used in the output section of the DCDC converter. Generally, at low temperatures below -20°C, the electrical conductivity of the electrolyte decreases and its viscosity increases, leading to a reduction in capacitance by several tens of percent, worsening frequency response, and increasing equivalent series resistance. As a result, it was determined that the transient response performance of the output voltage deteriorated, preventing the specified voltage from being achieved. [Countermeasures] - Confirm the capacitance, ESR, impedance, and frequency characteristics of the capacitor at low temperatures, and select an appropriate capacitor. *For more details, please refer to the PDF document or feel free to contact us.

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We would like to introduce a case where electrolyte leaked during use, causing a short circuit in the circuit board and resulting in capacitor failure. The electrolyte in aluminum electrolytic capacitors evaporates during operation, releasing gas into the atmosphere through the sealing rubber gasket. Additionally, aluminum electrolytic capacitors are equipped with pressure relief valves. Therefore, if the capacitor is covered with resin or similar materials, it can hinder the release of gas and the operation of the pressure relief valve. In this case, the coating material blocked the pressure relief valve, impairing its function and causing the sealing part of the capacitor to break, leading to electrolyte leakage. As a result, the circuit board wiring short-circuited, and the capacitor failed. **Countermeasures** - Do not cover the entire circumference of the capacitor with coating agents or resin. - Most of our aluminum electrolytic capacitors can withstand vibration tests with acceleration of up to 10G. *For more details, please refer to the PDF document or feel free to contact us.*

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We were using five aluminum electrolytic capacitors of the same rating and lot in parallel to eliminate ripple current, but I would like to introduce a case where one of these capacitors failed and the pressure relief valve was activated. Due to the constraints of the component layout on the circuit board, the failed capacitor was installed at a position away from the other capacitors. In that position, there were heat-generating components adjacent to it, and due to the radiant heat from these components, this capacitor was exposed to higher temperatures than the others. As a result, it experienced wear failure in a relatively short period, which caused the pressure relief valve to activate. [Countermeasures] - Review the mounting arrangement of the capacitors - Change the cooling method to mitigate the effects of radiant heat - It is recommended to use long-life capacitors that can handle high ripple currents *For more details, please refer to the PDF document or feel free to contact us.

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In this case, snap-in aluminum electrolytic capacitors were used in the power supply equipment, and to make the equipment thinner, the heat sink was closely positioned against the top of the capacitor. During a test for abnormal conditions in the equipment, an intentional overvoltage was applied to the capacitor, which caused the pressure valve located on the top of the capacitor to fail to operate and resulted in overheating. Subsequently, vapor from the electrolyte burst out from the grounding surface of the capacitor. The cause was that the capacitor shorted due to the overvoltage, leading to current flow and overheating. The heat vaporized the electrolyte, causing pressure inside the capacitor to rise, and since the pressure valve did not operate, gas from the electrolyte burst out from the sealing part of the capacitor on the grounding surface, shorting the wiring pattern on the substrate and causing a spark that resulted in smoke. [Countermeasures] - Review the requirements for the pressure valve to operate and the regulations for ensuring safety, and secure the necessary space. - If sufficient space cannot be secured, a type with a pressure valve on the side of the capacitor is recommended. *For more details, please refer to the PDF document or feel free to contact us.

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We will introduce a case where the capacity of aluminum electrolytic capacitors decreased in a circuit where the charging and discharging of capacitors, such as welding machines and strobe flashes, is frequently repeated. When charging and discharging aluminum electrolytic capacitors repeatedly, the following reactions continuously occur on the surface of the cathode foil. [During Charging] Gas generation due to the electrolysis of the electrolyte [During Discharging] The charge on the anode foil moves to the cathode foil, oxidizing the cathode surface As a result, internal pressure rises, leading to open failures when the pressure relief valve operates, or failures due to the decrease in capacity of the cathode foil, which reduces the capacitance of the capacitor. This phenomenon can occur not only during charging and discharging but also when a large voltage fluctuation is applied to the capacitor. [Countermeasures] ■ Use capacitors with specifications suitable for the charging and discharging circuit in circuits where frequent charging and discharging occurs. *For more details, please refer to the PDF document or feel free to contact us.

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We would like to introduce a case where an aluminum electrolytic capacitor used in the DC link of an inverter circuit overheated, causing the pressure relief valve to activate and the electrolyte to spray out from the capacitor. The cause was that a ripple current exceeding the allowable value flowed into the capacitor, causing it to overheat beyond its design specifications. Due to the overheating, the insulation deteriorated, leading to a short circuit, and the gas generated from the electrolyte increased the pressure inside the capacitor. The pressure relief valve activated, resulting in the electrolyte spraying out in aerosol form. **Countermeasures** - Confirm that the magnitude and waveform of the expected ripple current during the design phase match the specifications. - Select capacitors considering the allowable ripple current, temperature, and frequency corrections. *For more details, please refer to the PDF document or feel free to contact us.*

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We would like to introduce a case where the pressure relief valve of an aluminum electrolytic capacitor used in the power supply section operated and emitted smoke. The cause was that an overvoltage was applied to the aluminum electrolytic capacitor due to fluctuations in the input voltage, resulting in a short circuit of the capacitor. Current flowed through the capacitor, causing it to heat up and generate gas from the electrolyte. The pressure inside the capacitor increased due to the generated gas, causing the pressure relief valve to operate, and the electrolyte was ejected in aerosol form. 【Countermeasures】 <Check the voltage applied to the capacitor> ■ Is there any voltage fluctuation? ■ Does the peak value (V top) of the fluctuating voltage exceed the rated voltage? ■ Does the negative peak value (V bottom) of the fluctuating voltage exceed zero and become reverse voltage? ■ Is the range of fluctuation of the peak value excessively large? *For more details, please refer to the PDF document or feel free to contact us.

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Aluminum electrolytic capacitors are polarized capacitors with a limited lifespan that apply electrochemical operating principles, and they are also known as chemical capacitors. These capacitors have high volumetric efficiency (capacitance per unit volume), can achieve large capacitance values in the thousands of microfarads, can withstand large ripple currents, and have high reliability, making them suitable for a wide range of applications in DC circuits. On the other hand, it is necessary to consider their relatively high leakage current compared to other capacitors, a wide capacitance tolerance range of ±20%, high equivalent series resistance, and their finite lifespan when using them. Related catalogs provide detailed information on the features and structure of aluminum electrolytic capacitors and film capacitors. Please feel free to download and take a look. *For more details, please refer to the PDF materials or feel free to contact us.*

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Aluminum electrolytic capacitors are essential electronic components for power circuits and electronic circuits due to their small size and large capacity. Most aluminum electrolytic capacitors are polarized, so they are typically used in DC circuits. Their operating principle utilizes chemical reactions, and they are also known as chemical capacitors. As a result, the performance of aluminum electrolytic capacitors is greatly affected by environmental factors such as temperature and atmosphere, and failures can occur due to rapid chemical reactions. In the related catalog, we provide detailed explanations of failure cases of aluminum electrolytic capacitors and film capacitors, along with their causes, root causes, and countermeasures. Please take a look. *For more details, please refer to the PDF materials or feel free to contact us.*

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When a capacitor experiences a short circuit failure, it can no longer easily accumulate charge as current flows through it. For example, if a capacitor connected between the input side and ground to eliminate ripple current or noise shorts, a large current will flow from the input to ground. Causes of short circuit failures include applying voltage beyond the rated value, conducting ripple current, and usage under high temperature or high humidity. Additionally, for polarized capacitors, applying pure AC voltage or reverse voltage can also lead to shorts. Furthermore, because the dielectric of a capacitor is very thin, excessive mechanical stress can damage the dielectric and cause a short. It is important not only to consider electrical factors but also to ensure that the capacitor is not subjected to shocks or vibrations. Our related catalog provides a wealth of information on various failure phenomena and case studies, as well as factors and countermeasures. Please feel free to download and take a look. *For more details, please refer to the PDF materials or feel free to contact us.*

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When a capacitor fails open, the circuit becomes completely disconnected. For example, using a large-capacity capacitor in the power supply smoothing circuit can flatten a voltage waveform that resembles a large wave into a stable DC voltage. However, if the capacitor opens, high voltage may be applied to the circuit, potentially causing semiconductor failure. The main causes of open failure are disconnection or a significant increase in resistance. These often occur at the connection points between the capacitor's external terminals and the wiring. Since the external terminals, internal wiring, and structure vary depending on the type of capacitor, there are various types of open failures. In addition to usage of the capacitor, factors such as vibrations or shocks during transport, and the arrangement of equipment on the circuit board can also contribute to open failures. Our related catalog provides a wealth of information on various failure phenomena and cases, as well as causes and countermeasures. Please feel free to download and take a look. *For more details, please refer to the PDF materials or feel free to contact us.*

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AICTech's capacitors apply strict quality control and safety standards in the design and manufacturing of their products. However, with current technology levels, it is difficult to achieve zero failures in capacitors. When a failure occurs, the capacitor loses its basic functions of storing charge in direct current and eliminating noise and ripple current. In the worst case, there is a risk of ignition leading to a fire. If you notice conditions such as "cracks in the case" or "smoke coming out," it indicates a failure, and you must immediately disconnect the power and take appropriate action. The related catalog explains the phenomena and causes of failures, as well as examples of countermeasures, to help you use capacitors properly. Please take a moment to read it. *For more details, please refer to the PDF document or feel free to contact us.*

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A capacitor is one of the fundamental and important components in electronic circuits. For engineers involved in circuit design, accurately acquiring knowledge about the characteristics and properties of capacitors is essential for product development. However, when reconsidering the basic operation and mechanisms of capacitors, one might realize that there are oversights and misunderstandings. We will provide an "Introduction to Capacitors You Can No Longer Ask About," covering everything from the basic structure, mechanisms, and design of capacitors to the units used to express the size of capacitors, including the currently popular large-capacity capacitors. *For more details, please refer to the PDF materials or feel free to contact us.*

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When a capacitor fails, electronic devices may not operate as expected, potentially leading to unexpected accidents. However, it is impossible to eliminate capacitor failures entirely. Therefore, our company, which has been manufacturing capacitors for about 70 years, will introduce the causes of failures and examples of countermeasures to ensure that capacitors are used appropriately and safely. [Failure Phenomena and Examples, Causes and Countermeasures] ■ Smoke emitted from a capacitor that shorted due to overvoltage ■ A capacitor failed due to excessive ripple, causing electrolyte to spray out ■ A capacitor in the charge and discharge circuit lost its capacitance ■ A pressure valve failed to operate, causing steam to erupt from the grounding surface ■ One of the capacitors connected in parallel failed ■ The characteristics of an aluminum electrolytic capacitor decreased at low temperatures ■ The characteristics of an aluminum electrolytic capacitor deteriorated after long-term storage ■ An aluminum electrolytic capacitor sparked ■ An aluminum electrolytic capacitor installed horizontally burst ■ An aluminum electrolytic capacitor connected in series shorted ■ A film capacitor intended for DC use failed when used in an AC circuit ■ A resin-coated film capacitor ignited *For more details, please refer to the PDF document or feel free to contact us.

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We would like to introduce our "Plastic Film Capacitors." We offer a wide range of products, including large-capacity cylindrical capacitors suitable for wind power generation, solar power generation, various inverters, chopper control, and charging/discharging, such as the "MLC type." Additionally, we have resin case capacitors suitable for DC link circuits and box-type capacitors in our lineup. 【Plastic Film Capacitor Lineup (Partial)】 ■ MLC type ■ MLC2 type ■ MLCA type ■ MKCP4 type ■ MKCP4T type *For more details, please refer to the PDF document or feel free to contact us.

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We would like to introduce the "Aluminum Electrolytic Capacitors" that we handle. The screw terminal type aluminum electrolytic capacitors have a heat dissipation structure that improves ripple current by approximately 10% compared to the HCGF6A type, including the "VF type" and many others such as the "VG type." Additionally, we offer a lineup of board-mounted aluminum electrolytic capacitors with an 85°C, 2000-hour guarantee, as well as lead type aluminum electrolytic capacitors. 【Screw Terminal Type Aluminum Electrolytic Capacitors Standard Product Lineup (Partial)】 ■ VF type ■ VG type ■ VFL type ■ VGL type ■ VFH type *For more details, please refer to the PDF document or feel free to contact us.

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This is an introduction to the basic knowledge of capacitors, which have a structure with a dielectric sandwiched between two opposing electrodes. The capacitance of capacitors will be explained using diagrams, and the characteristics of various capacitors and environmentally friendly products will be discussed using tables. Our company promotes environmental management based on CSR (Corporate Social Responsibility), with the philosophy of harmonizing corporate activities and the environment. In terms of product offerings, we provide lead-free products that do not contain lead in the product terminals, as well as products that do not contain polyvinyl chloride in the exterior materials. Our standard lineup includes products that comply with the European RoHS Directive (2011/65/EU and 2015/863/EU, etc.). *For more details, please refer to the PDF materials or feel free to contact us.

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This catalog is a comprehensive catalog featuring capacitors handled by AIC Tech Co., Ltd. We offer lead-free products that do not contain lead in the product terminals, as well as products that do not include polyvinyl chloride in the exterior materials, all of which comply with the European RoHS Directive (2011/65/EU and 2015/863/EU, etc.) as standard products in our lineup. [Contents] ■ Aluminum Electrolytic Capacitors - Screw terminal aluminum electrolytic capacitors - PCB mount aluminum electrolytic capacitors - Lead terminal aluminum electrolytic capacitors ■ Plastic Film Capacitors - Plastic film capacitors for power electronics, etc. *For more details, please download the PDF or feel free to contact us.

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