Introduce the types and applICation advantages of pads in PCB
Introduction to pad types in PCB board and application advantages
Circular pads-widely used in single and double-sided printed boards with regularly arranged components.  If the density of the circuit board allows, the pad can be larger so that it will not fall off during welding
The connection between the island liner and the liner is integral It is usually used for installation with vertical irregular arrangement For example, this kind of cushion is usually used in tape answering machines
Polygonal gaskets are used to distinguish gaskets with SIMilar outer diameters but different apertures for processing and assembly
Oval liner The liner has enough area to enhance the anti stripping ability, and is usually used for dual in-line equipment
Open the formed pad to ensure that the manually repaired pad hole is not seaLED with solder after wave soldering
When printed circuit board components are large and few, square pads are more used, and the printed circuit is simple This pad is easy to use when making PCB manually
PCB boards

Plum blossom pad
1. The fixing hole needs to be nonmetallic During wave soldering, if the fixing hole is a metallized hole, tin will block the hole during reflow soldering
2. Fixing the mounting hole as a quincunx pad is usually used for mounting hole GND network, because generally, PCB copper wire is used for laying GND network copper wire After installing the quincunx hole with PCB housing assembly, in fact, GND is grounded Occasionally, the PCB housing acts as a mask Of course, some do not need to connect the mounting hole to the GND network
3. The metal screw hole may be squeezed, resulting in the grounded and ungrounded zero boundary state and system abnormality No matter how the pressure changes, the screw can always be grounded
Cross mode pad: Cross mode pad is also called hot pad, hot air pad, etc Its function is to reduce heat dissipation of pads during welding, so as to prevent false soldering or PCB peeling due to excessive heat dissipation
Introduction to pad types in PCB board and application advantages
1. When your mat is grounded The cross mode can reduce the area of the ground wire, reduce the heat dissipation speed, and facilitate welding
2. The cross pattern pad can prevent the PCB from peeking (because more heat is needed to melt the solder paste) when your PCB needs to be placed and is a reflow soldering machine
Teardrop pad: Teardrop is an excessive drip connection between pad and wire or between wire and through hole The purpose of setting teardrops is to prevent the wires and pads or wires from being impacted by huge external forces The contact point of the pilot hole is disconnected, and the teardrop placement can also make the PCB look more beautiful
1. Protect the pad during welding to avoid the pad falling off due to repeated welding
2. Strengthened the reliability of the connection (production can avoid cracks, etc.)
3. Smooth impedance and reduce the sharp jump of impedance
In the circuit board design, in order to make the base plate more solid and prevent the base plate and wire from being disconnected in the mechanical manufacturing process of the circuit board, the copper film is usually used to arrange the transition area between the pad and the wire, which is shaped like a teardrop, so it is usually called teardrop filling

The above is the explanation given by the editor of pcb circuit board company.
If you want to know more about PCBA, you can go to our company's home page to learn about it.
In addition, our company also sells various circuit boards,
High Frequency Circuit Board and SMT chip are waiting for your presence again.