Leiterplattentechnisch - Verwandte PCB-Technologie Forschung

Verwandte Leiterplattentechnologie research
Process method
For some areas where the device is mounted on both sides, Es ist leicht, lokale hohe Temperatur zu verursachen. Zur Verbesserung der Wärmeableitungsbedingungen, Eine kleine Menge an kleinem Kupfer kann in die Lötpaste gemischt werden, und die Lötstellen unter dem Gerät haben nach dem Reflow-Löten eine bestimmte Höhe. Der Abstand zwischen dem Gerät und dem bedruckte Pappe erhöht wird, und die Konvektionswärmeableitung wird erhöht.
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 Leiterplatte;
(3) The heat capacity of the board is evenly distributed. Achten Sie darauf, Hochleistungsgeräte nicht konzentriert zu platzieren. Wenn es unvermeidlich ist, 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 bedruckte Pappe. Wenn möglich, Sie sollten auf dem Heizkörper installiert werden, weit weg von anderen Komponenten, 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 bedruckte Pappe 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. Aus diesem Grund, die Wärmeleitungsfläche sollte vergrößert werden; Die Kontaktfläche sollte flach und glatt sein, und kann bei Bedarf lackiert werden.
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 bedruckte Pappe Um die Befestigungsschrauben und die Kupferfolie auf der Oberfläche des bedruckte Pappe for heat dissipation;
(10) Place as many metalized vias as possible, und die Öffnung und die Scheibenoberfläche sollten so groß wie möglich sein, 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≤(0.5～0.8)tjmax).
4. Thermal simulation (thermal analysis)
Thermal analysis can help designers determine the electrical performance of components on the PCB, und helfen Konstrukteuren zu bestimmen, ob Komponenten oder PCBs wird durch hohe Temperaturen ausbrennen. Einfache thermische Analyse berechnet nur die Durchschnittstemperatur der PCB, Während komplexe Modelle die Etablierung transienter Modelle für elektronische Geräte erfordern, die mehrere PCBs und Tausende von Komponenten.