PCB resin plug via always has voids problems, it lead to solder area reduce and bring soldering reliability problems.The article analyses the generation factors of voids and how to improve it?
Via in pad technology is used in high frequency design to reduce inductance and increase density, means via plug is
It's very important how to calculate impedance value before PCB fabrication.
What is impedance?
Impedance is the total resistance of alternating current produced at known frequency.it's resistance sum of signal layer and reference plane.
Impedance Type
Characteristic impedance
Characteristic impedance is the ratio of voltage and current of a single wave propagating along the line.Signal produces reflection in the impedance discontinuity
PCB surface treatment ensure circuit board had good solderability or electrical property.Due to the nature of the copper oxide form tend to be in the air, it’s impossible to maintain the original copper,so copper requiring additional processing. Below is the most popular PCB surface treatment.
HASL and HASL-LF
HASL is hot air
Some comments for select PCB materials:
For electronic products, using FR4 epoxy fiberglass materials.
For high temperature application or flexible circuit board, using polyimide materials.
For high-frequency circuit, using Rogers or Teflon materials.
For high heat dissipation products, using metal core materials,like Al based material.
Five factors we should consider when
