| 摘要 |
PURPOSE: A USB modem is provided to embody a stable and excellent communication quality by blocking EMI(Electro Magnetic Interference). CONSTITUTION: A USB modem comprises a circuit board(400), a shield(200), and an EMI blocking unit(300). The shield(200) is placed between the case covering the circuit board, and have a vertex which meets with at least more than one vertex of the circuit board. An EMI blocking unit placing on a shield surface or inside of the case blocks EMI generated from an electricity parts on a circuit board. |
