Switching power supply PCB design specifications
In any switching power supply design, PCB board design is the last physical link, if improper design, PCB
May radiate excessive electromagnetic interference, resulting in unstable power supply, note the following things required for each step
Analysis items:
First, the establishment of component parameters from the schematic to the PCB design process -> Input principle netlist -> Design parameters > Manual Layout -> manual routing -> validate design -> Review -> CAM output.
Second, the parameters must be able to meet the conductor spacing of adjacent electrical safety requirements, and in order to facilitate the operation and production, spacing These should be as wide as possible. The minimum distance of at least be able to withstand the appropriate voltage, the wiring density is low, the pitch of the signal line Can be appropriately increased to high and low disparity signal lines should be as short as possible and increase the spacing, will go under normal circumstances Line spacing set 8mil. The inner side of the hole edge of the pad of the printed circuit board is greater than the distance to 1mm, to avoid defects in the processing of lead pads. When the welding When the alignment plate connection is fine, the connection you want to walk the line between the pad and into a teardrop-shaped design, this benefit is not pad Easily from the skin, but not easy to go off line and pad.
Third, the components layout proved, even if the circuit schematic design properly, improperly printed circuit board design, also on the power
Adversely affect the reliability of the child device. For example, if the PCB two thin parallel lines are very close, it will form a channel No. waveform delay in forming a transmission line terminal reflection noise; due to power, ground caused by thoughtless Interference, the product will decrease performance, therefore, when designing the printed circuit board should be noted in the right way. Each has four current switching power supply circuit: (1) Power Switch AC circuit (2) output rectifier AC circuit (3) current loop input source (4)Output load current loop input circuit by an approximate DC input capacitor charging current, mainly from the filter capacitor A wideband energy storage effect; Similarly, the output of high frequency filter capacitor is also used to store energy from the rectifier output, While eliminating the DC power output load circuit. Therefore, the terminal input and output filter capacitor is very important, lose Income and output current loops should be the only difference from the terminal filter capacitor connected to the power supply; If the input / output circuits and power
Source switch / rectifier circuit connected between ......
Switching power supply PCB design specifications _ download
