Tecnología de PCB - Investigación sobre la tecnología conexa de PCB

Pertinente Tecnología de Placa de circuito impreso research
Process method
For some areas where the device is mounted on both sides, Fácil de causar altas temperaturas locales. Para mejorar las condiciones de disipación de calor, Una pequeña cantidad de cobre se puede mezclar en la pasta de soldadura, Después de la soldadura reflow, la Junta de soldadura por debajo del dispositivo tendrá cierta altura. Equipo y Placa de circuito impreso Aumento, Aumento de la disipación de calor por convección.
3...3 Requirements for the arrangement of components
(1) Perform software thermal analysis on Placa de circuito impreso, 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 Placa de circuito;
(3) The heat capacity of the board is evenly distributed. Tenga cuidado de no centrarse en dispositivos de alta potencia. Si es inevitable, 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 Placa de circuito impreso. Si es posible, Deben instalarse en el radiador, Manténgase alejado de otros componentes, 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 Placa de circuito impreso 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. Por esta razón, Ampliar la zona de conducción de calor; La superficie de Contacto debe ser plana y Lisa., Se puede pintar si es necesario.
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 Placa de circuito impreso Hacer pleno uso de los pernos de montaje y Placa de circuito impreso for heat dissipation;
(10) Place as many metalized vias as possible, El diámetro del agujero y la superficie del disco deben ser lo más grandes posible, 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 ⅱž0.8)tjmax).
4. Thermal simulation (thermal analysis)
Thermal analysis can help designers determine the electrical performance of components on the Placa de circuito impreso, Y ayudar a los diseñadores a identificar componentes o Placa de circuito impresoS se quemará a altas temperaturas. Análisis térmico simple sólo cálculo Placa de circuito impreso, El circuito complejo necesita construir el modelo transitorio del equipo electrónico que contiene múltiples componentes. Placa de circuito impresoS y miles de componentes.