The invention discloses a
ceramic filter
electromagnetic shielding device for SIP (
Session Initiation Protocol) internal lamination
assembly and a preparation method thereof. The device comprises a
metal shielding body, a
copper-clad layer, a metalized through hole and a bottom layer printed board cavity, the preparation method comprises the following steps: adding
copper-clad
layers on the outer sides of non-transmission structures on two sides of a
ceramic filter circuit, interconnecting the
copper-clad
layers with a large-area grounding bonding pad on the back surface of the
ceramic filter through a row of metalized through holes, and bonding a
metal shielding body on the upper surface of the ceramic filter by using
welding flux on the copper-clad
layers to form a semi-closed body; increasing the thickness of the bottom-layer printed board by utilizing the height of the space in the SIP tube shell, and digging a cavity meeting the size of the assembled ceramic filter on the bottom-layer printed board; and a semi-closed body formed by the ceramic filter and the
metal shielding body is arranged in the cavity of the bottom-layer printed board to form the
electromagnetic shielding device of the ceramic filter. The
radio frequency performance of the ceramic filter is improved, the
electromagnetic shielding performance of the ceramic filter is improved, and the ceramic filter is easy to process and assemble and high in reproducibility.