What is the breakdown voltage of Cbb21 105j400v?
Oct 07, 2025| Hey there! As a supplier of Cbb21 105j400v capacitors, I often get asked about the breakdown voltage of these little guys. So, I thought I'd take a few minutes to break it down for you (pun intended).


First off, let's talk about what a Cbb21 105j400v capacitor is. The "Cbb21" refers to the type of capacitor, which is a metalized polypropylene film capacitor. These capacitors are known for their high reliability, low loss, and excellent self-healing properties. The "105" indicates the capacitance value, which is 1 microfarad (1000000 picofarads). The "j" represents the tolerance, which is ±5%. And the "400v" is the rated voltage, meaning this capacitor is designed to operate safely at up to 400 volts.
Now, the breakdown voltage is a different story. The breakdown voltage is the voltage at which the dielectric material in the capacitor breaks down, allowing current to flow through it in an uncontrolled way. This can cause the capacitor to fail, and in some cases, it can even lead to a short circuit or other serious problems.
For a Cbb21 105j400v capacitor, the breakdown voltage is typically higher than the rated voltage. In general, you can expect the breakdown voltage to be around 1.5 to 2 times the rated voltage. So, for a 400v rated capacitor, the breakdown voltage might be in the range of 600 to 800 volts.
But here's the thing: the breakdown voltage isn't a fixed value. It can vary depending on a number of factors, including the quality of the materials used, the manufacturing process, and the operating conditions. For example, if the capacitor is exposed to high temperatures, high humidity, or other harsh environmental conditions, the breakdown voltage might be lower than normal.
That's why it's important to choose a high-quality capacitor from a reputable supplier. At our company, we take great care to ensure that our Cbb21 105j400v capacitors are manufactured to the highest standards. We use only the best materials and the latest manufacturing techniques to ensure that our capacitors have a high breakdown voltage and a long service life.
Another thing to keep in mind is that you should always use a capacitor with a rated voltage that is higher than the maximum voltage that will be applied to it in your circuit. This provides a safety margin and helps to prevent the capacitor from breaking down.
Now, let's talk about some of the applications for Cbb21 105j400v capacitors. These capacitors are commonly used in a variety of electronic devices, including power supplies, audio amplifiers, and lighting fixtures. They are also used in motor control circuits, where they help to smooth out the current and reduce electromagnetic interference.
If you're looking for a reliable and high-quality Cbb21 105j400v capacitor, you've come to the right place. We offer a wide range of capacitors, including CBB21-Film Capacitor 400V, CBB21-Film Capacitor 160V, and Mkp Capacitor. Our capacitors are available in a variety of capacitance values, tolerances, and voltage ratings to meet your specific needs.
We also offer competitive pricing, fast shipping, and excellent customer service. Whether you're a small electronics hobbyist or a large-scale manufacturer, we can provide you with the capacitors you need at a price you can afford.
So, if you're interested in learning more about our Cbb21 105j400v capacitors or any of our other products, please don't hesitate to contact us. We'd be happy to answer any questions you might have and help you find the right capacitor for your application.
In conclusion, the breakdown voltage of a Cbb21 105j400v capacitor is an important factor to consider when choosing a capacitor for your circuit. By understanding the breakdown voltage and choosing a high-quality capacitor from a reputable supplier, you can ensure that your circuit operates safely and reliably.
References:
- Capacitor Basics: Understanding Capacitance, Voltage, and Tolerance
- Metalized Polypropylene Film Capacitors: Features and Applications
- Electronic Component Handbook

