| 摘要 |
<p>Terminal equipment (10) for telecommunications and information processing with improved electromagnetic compatibility (EMC). The equipment has a human-machine interface (HMI), connected via HMI cables 31 and 32, a metallic telecommunications interface (TCI), connected via TCI cable 41, and optionally a power line interface (PLI), connected via PLI cord 42. First common-mode rejection filters (Lc11, C11, C13; Lc12, C12, C14) comprising common-mode choke coils (Lc) and shunt capacitors (C) are placed at the HMI interface of the equipment, while second common-mode rejection filters (Lc21, C21, C23; Lc22, C22, C24) comprising the same components are placed at the TCI and PLI interfacces. High-frequency junction points (P1-P4) of the fisrt and second common-mode rejection filters are interconnected with a bypass circuit (BG). Being isolated from the signal ground (SG) and frame ground (FG) of the equipment, the bypass circuit (BG) is an independent non-grounded circuit. Such internal structure makes it possible to reject noise signals induced by an external noise source and also to suppress spurious radiation from an internal noise source. <IMAGE></p> |
