PCB技術 - 関連PCB技術研究

関連 PCB技術 research
Process method
For some areas where the device is mounted on both sides, 局部的な高温を起こしやすい. 放熱条件を改善するために, 少量の小さな銅をはんだペーストに混入させることができる, そして、デバイスの下のハンダ接合はリフローはんだ付けの後、ある高さを有する. 装置と装置の間の隙間 プリント板 増加, そして、対流熱放散が増加する.
3.3 Requirements for the arrangement of components
(1) Perform software thermal analysis on PCB, and design and control the internal maximum temperature rise;
(2) It is possible to consider specially designing and installing components with high heat generation and large radiation on a printed 回路基板;
(3) The heat capacity of the board is evenly distributed. 高出力デバイスを集中的に配置しないように注意してください. それが避けられないならば, place the short components upstream of the airflow and ensure that sufficient cooling air flows through the heat-consumption concentrated area;
(4) Make the heat transfer path as short as possible;
(5) Make the heat transfer cross section as large as possible;
(6) The layout of components should take into account the influence of heat radiation on surrounding parts. Heat sensitive parts and components (including semiconductor devices) should be kept away from heat sources or isolated;
(7) (Liquid medium) It is best to keep the capacitor away from the heat source;
(8) Pay attention to the direction of forced ventilation and natural ventilation;
(9) The additional sub-boards and device air ducts are consistent with the ventilation direction;
(10) Make the intake and exhaust as far away as possible;
(11) The heating element should be placed above the product as much as possible, and should be placed on the air flow channel when conditions permit;
(12) Components with high heat or high current should not be placed on the corners and peripheral edges of the プリント板. できれば, 彼らはラジエーターに設置されるべきだ, 他のコンポーネントから遠く離れて, and ensure that the heat dissipation channel is unobstructed;
(13) (Small signal amplifier peripheral devices) Try to use devices with small temperature drift;
(14) Use metal chassis or chassis as much as possible to dissipate heat

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3.4 Requirements for wiring
(1) Board selection (reasonable design of プリント板 structure);
(2) Wiring rules;
(3) Plan the minimum channel width according to the current density of the device; pay special attention to the channel wiring at the junction;
(4) The high-current lines should be as surface as possible; if the requirements cannot be met, the use of bus bars can be considered;
(5) Minimize the thermal resistance of the contact surface. この理由から, 熱伝導域を拡大する接触面は平坦で滑らかでなければならない, 必要なら塗装することができます.
Coated with thermal grease;
(6) Consider the stress balance measures for thermal stress points and thicken the lines;
(7) The heat-dissipating copper skin needs to adopt the window method of heat dissipation stress, and use the heat-dissipating solder mask to open the window properly;
(8) If possible, use large-area copper foil on the surface;
(9) Use larger pads for the ground mounting holes on the プリント板 取付ボルトや銅箔を全面的に利用する プリント板 for heat dissipation;
(10) Place as many metalized vias as possible, そして、アパーチャとディスク面は、できるだけ大きくなければなりません, relying on vias to help heat dissipation;
(11) Supplementary means for device heat dissipation;
(12) In the case where the large surface area of copper foil can be used, the method of adding a heat sink may not be used for economic reasons;
(13) Calculate the appropriate surface heat dissipation copper foil area according to the power consumption of the device, the ambient temperature and the maximum allowable junction temperature (guarantee principle tj≤(0.5回1 / 2.8)tjmax).
4. Thermal simulation (thermal analysis)
Thermal analysis can help designers determine the electrical performance of components on the PCB デザイナーがコンポーネントかどうかを判断する PCBsは、高温のため燃え尽きます. 単純な熱分析は PCB, 複雑なものは多重を含む電子デバイスの過渡モデルの確立を必要とする PCBsと何千もの構成要素.