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About PCB and PCBA

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PCB and PCBA A PCB (Printed Circuit Board) is a board that electrically connects electronic components using conductive traces, pads, and other features etched from copper foil laminated onto a non-conductive substrate. PCB’s can be  single sided  (one copper layer),  double sided  (two copper layers), or  multi-layer  (outer and inner layers). Conductors on different layers are connected with vias (plated-thru. holes). Multi-layer PCB’s allow for much higher component density and design complexity. PCBA (Printed Circuit Board Assembly) is the board obtained after all printing solder paste on the PCB and then mounting various components like resistors, ICs (Integrated Circuits), capacitors and any other components  like transformers depending on the application and desired characteristics of the board. A PCBA usually undergoes reflow furnace heating to establish a mechanical connection between the PCB and the components.

10. The design of PCB (multiple layer board)--Basic requirement of designing multiple layer PCB VOL2

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The requirements of wire cloth and wiring   Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)  In general, PCB multilayer board wiring is performed according to circuit function. In outer wiring, it is required to have a lot of wiring in the welding surface, and the components are less wiring, which is beneficial to the maintenance and platoon of printing plate. Thin, tight conductor and easily disturbed signal lines, usually arranged in the inner layer. The large area of copper foil should be evenly distributed in the outer layer, which will help to reduce the warping of the plate and make the plating more uniform on the surface. In order to prevent the short circuit between the surface and the printed wire and the mechanical processing, the distance of the conductive graph in the inner and outer layers should be greater than 50mil. Wire direction and line widt...

Product--RMF69 Shield

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RMF69 Shield-433MHz contains a FSK wireless module, it has the same function that radio frequency transmitter owns, such as receiving and transmitting message. RMF69 Shield-433MHz can totally compatible to Arduino. Features Low consumption More professional ISM band Frequent range from 140 to 960MHz  Totally compatible to Arduino http://juvtmall.com/rfm69-shiled_p0808.html

Product--SIM808

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Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)  The SIM808 GPRS/GSM+GPS Shield V1.0 is based on the chip named SIM808, it communicates with Catduino Uno via pins (RX, TX) with GPS data and GPRS data. For the operate voltage could either at 3.3V or 5V, it can be totally compatible to the Arduino. It can be also used to making/answering call, sending/receiving SMS messages and local the position. By the way, SIM GPRS/GSM+GPS Shield V1.0 suppose an SIM card holder at the opposite side. http://juvtmall.com/sim808-btgsmgps-sheild_p0813.html

8. The design of PCB (multiple layer board)---Method of wring and necessary work

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2.  Method of wiring on multiple layers PCB       Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)     Generally, four layers board can be divide into top layer, bottom layer and two internal layer. Internal layer: by command “DESIGN/LAYER STACK MANAGER” use “ADD PLANE” add “INTERNAL PLANE1” and “INTERNAL PLANE2” as VCC and GND in power and GND layer (tip: don’t use “ADD LAYER”, it will add MIDPLAYER, it’s used in multiple layer of signal track), if there are several power layer such as VCC2 or GND layer such as GND2, then use bolder wire or FILL to draw a district on power of GND belongs to PLANE1 or PLANE2,  use PLACE/SPLIT PLANE to make a corresponding district (VCC2 copper and GND2 copper flakes are not present in this area in the same PLANE) tip: different surface layers in the same PLANE and try not to overlap.SPLIT1 and SPLIT2 are overlappe...

6. The design of PCB-- related skills

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9. PCB design related skills   Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)  PCB design setting technique The PCB design needs to be set different points  in different stages. In the layout phase, the device layout can be used in the large lattice point . For large devices such as IC and non-locating connectors, the lattice site of 50~100mil can be selected for layout, and the grid point of 25mil can be used for the distribution of passive devices such as resistance capacitance and inductance. The precision of the large lattice point is beneficial to the orderliness and beauty of components. PCB layout rules 1. In general , all components shall be decorated on the same side of the boards, only the top-level element too close, set some highly limited and calorific value small devices o n the bottom., such as SMD resistor, SMD capacitors, SMD IC, etc. 2....

5. The design of PCB--design considerations and assembly rules

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. PCB design considerations   Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)  (1) avoid setting important signal lines on the edge of PCB, such as clock and reset signal. (2) the distance between the ground wire of the enclosure and the signal line is at least 4mm; keep the length and width of the ground wire to be less than 5:1 to reduce the inductance effect. (3) lock the device and line that identified location with LOCK function, so that they will not be misused. (4) the width of the conductor should not be less than 0.2mm (8mil). In high-density and high-precision printed circuit, the width and spacing of the wires are generally preferable to 12mil. (5) Routing in the IC pin of DIP package, 10-10 and 12-12 principles can be applied, as between the two pins by 2 lines, diameter of bonding pad  can be set to 50 mil, width and spacing of line is 10 mil, when o...

4. The design of PCB-- PCB design related concepts

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6. PCB design related concepts Juvtmall  ( a company supply  PCB Prototyping ,  PCBA service  and sell kinds of  components, modules  and so on)  Via  holes: Once selected, be sure to deal with the gap between it and the surrounding each entity especially easy to ignore the gap between the line not connected to via hole of each layer in the middle   and via hole, if it is a automatic wiring, can be in "number Via minimization" (Via Minimiz8tion) in the sub menu select "on" to automatically solve. The larger load flow required, the larger hole size required, such as the larger the hole in the power layer and the other layer. Silk screen layer: For the convenience of installation and maintenance of the circuit, etc., it need s   printing logo and  writing code   on the upper and lower surface of the printing circuit , such as component label and nominal value,   the profile  of   the component and th...