Share 10 considerations of PCB panel for fabrication:
1, frame of PCB panel should use the design of closed loop,to ensure that PCB will not be deformed after fixing on fixture
2, the width of pcb panel ,for SIEMENS line, should be not more than 260mm ;for FUJI line, should be not more than 300mm.If it needs automatic dispensing,width *length should be not more than 125mm*180mm.
3, The shape of PCB panel try to close to square shape.We recommend using the panel of 2*2 and 3*3.
4, the center distance of the small board shoule be controlled between 75 mm and 145 mm.
5, When we set the base location point, usually leave solder-free zone where is more than 1.5mm than the base location point.
6, The junction ,between panel frame and inner small board,between small boards , does not have large components or protruding components.And the edge of components and pcb should have the space of more than 0.5mm,to ensure the normal operation of the cutting tool.
7, Make four positioning holes in the four corners of panel frame.The diameter is 4mm,and its tolerance is + 0.01mm. The strength of the hole should be moderate, to ensure that the holes can not be broken in the process of loading and unloading the board.Precision of aperture and position should be high.The hole wall should be smooth and burr-free.
8, Each small board in PCB panel should have at least three positioning holes,and its aperture is between 3mm and 6 mm. The place within 1mm of edge location does not allow wiring or patch;
9 Datum symbol is used for positioning of the entire board and fine-pitch devices .In principle,QFP with the space of less than 0.65mm should be set on diagonal position.The datum symbol should be used in pairs,and should be set on diagonal position of positioning elements.
10, Large components should have positioning column or positioning holes,such as I / O interface, microphone, battery connector, micro switch, headphone jack,and a motor.
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