What are the rules for PCB optical board wiring layout

The wiring layout of Pcb board is one of the most important factor for operation well or not. Pcb wiring is to lay printingwires according to the electrical schematic diagram and the conductor meter， as well as the required conductor width and spacing. Generallyshould follow below rules when layout wire:

1.On the premise of satisfying the usage requirement ,theorder of choosing wiring mode is single→layer one→layer multi-layer, it meansif wiring can be simplifydonot make it complicate.

2.The signalon the same layer of the Pcb boardchange direction with oblique or smooth transition, and largercurvature radius isbetter, which avoids electric field concentration, signal reflection and additional impedance.

3.The wires between two solderingpads should be designedas short as possiblethat the sensitive and small signals coveypreferentially in order toreduce the delay and interference of small signal. Ground wire shielding should be placed beside the input wireof analog circuit, and the same layer wiresshould be evenly distributed. The conductive area of each wire should be relatively balanced to prevent the board from warping.

4.Digital circuits should be separated fromanalog circuitsfor wire layout to avoid interference mutually.

5.The circuit elements on the Pcba board should be grounded and connected to the power supply as short and close as possible, so that reduce the internal resistance of the PCB board.

6.Thelength of I/O wires of high-speed circuit, differential amplifier and balanced amplifier should be same to avoid unnecessary delay or shift.

7.The wiresof each layer on the multi-layer board should be perpendicular to each other in order to reduce coupling and avoid line-up or balance between upper and lower layers.

8.The thin wire should be not shorterthan 0.5mmwhen it’s used for thermal isolation, and the thin wirewidth should not be less than 0.13mm,when the soldring pad is connected with the large and small conductive area.

9.The conductor which is most closest to the edge of PCB,should be over5 mm from the edge of PCB, and the grounding wire can be close to the edge of PCB when it is needed.The distance between the wire and the edge of the board is at least deeperthan the depth of the guide grooveif the PCB is inserted into the guideduring processing.