TDK used its strength of being the first manufacturer in the world to commercialize ferrite, and developed a high performance ferrite material best suited for products. We are developing choke coils for PFC (power factor correction) circuit that utilize this characteristics to its fullest potential. To conform to downsizing, thinning, or minimizing floor space which are the requirements for various electronic devices, original core shape products with sufficient DC superposition characteristics for design are included in the lineup as standard products. By supporting automated winding design, stable high quality supply with little variation is made possible compared to conventional construction methods.