The present invention relates to a choke with two coils and a core for interleaved applications in step-up or step-down circuits or power factor compensation circuits. The core comprises several core sections with several lateral legs and a middle leg, whereby the core is designed such, that a coupling factor k of the two coils is smaller than 3%-5%. Furthermore, the core is designed such, that the core section form two loops with the middle leg as a common section, whereby each of the two coils lies on different loops outside of the common section. The lateral legs have a cross section A1 and the middle leg for the common section has a cross section A2