Yunpen Electronic Company was established in 1990 by a group of experts with over 26 years of electronic engineering experience and specializing in the design and production of various high and low pass EMI filters and cores. We have earned a reputation in the worldwide industrial community as a quality ISO-9000 supplier. In order to reduce cost and remain competitive, we have built an EMI filter and core factory in Mainland China, with a monthly production ability of up to 1 million EMI filters for a variety of equipment manufacturer's needs. The US branch office was established in Southern California in 1999 to improve our customer service, order efficiency and increase sales in North America.

Because of the fast development and implementation of high-technology, every factory, business and home is using more electronic equipment, personal computers, communication devices, medical equipment, testing instruments, and all kinds of automatic devices. Today, it is rare for an electronic device to be used in isolation; they are networked and grouped into communities for efficiency and control. With these communities comes interference problems due to the close proximity and shared circuits. This interference between electronic devices and circuits is getting serious; EMI and noise are the most obvious and distracting problem. In addition, the improvement of Integrated Circuits diminishes the physical size of electronic devices allowing for more equipment in smaller spaces, increasing the chance of interference.

The wide use of digital systems, especially computers and high-efficient switching power supplies can cause severe EMI problems. How to increase Electro Magnetic Compatibility (EMC) has become the new objective for electronic engineers. Yunpen believes that it is better to prevent a problem than to correct it afterwards. Therefore, we carefully select materials and strictly control the products' quality during every step of production to assure its excellence. We develop new EMI filter models every year to fit the present and future needs of our customers. Yunpen welcomes the cooperation of OEMs and we gladly accept and produce the designs of our clients. In addition, we produce a variety of ferrite cores, according to the AL value, the specifications, and the functions that our clients provide. Yunpen can build it for you.