Different Types Of Printed Circuit Board Vias - Miracle Aerospace - PowerPoint PPT Presentation

About This Presentation
Title:

Different Types Of Printed Circuit Board Vias - Miracle Aerospace

Description:

Via, one of the most important components of a PCB, can be plated and crafted in various ways. This blog will let you know the most common types of Vias – through hole, blind hole, buried hole, stub Via, and back-drilled Via. – PowerPoint PPT presentation

Number of Views:150

less

Transcript and Presenter's Notes

Title: Different Types Of Printed Circuit Board Vias - Miracle Aerospace


1
Different Types Of Printed Circuit Board Vias
Miracle Aerospace
Via is one of the most important components of a
multi-layered printed circuit board (PCB), whose
cost of drilling can range between 30-40 of the
total board cost. A PCB has layers of copper
foil circuits stacked on top of one another, with
each layer being connected through the Via. This
Via is plated in different ways, with the most
common ones being plating through hole, plating
through blind hole, and plating through buried
hole. Then, there are other stub and
back-drilled Vias too. Well learn about all of
this in detail here. And, whatever your choice,
you can get the best quality PCB assembly from
India at Miracle Aerospace, a name known for the
finest electronic manufacturing services in the
country.
Plating through hole This is the most common
plating method, which is also the simplest kind
of plating as it needs only a drill or laser
light to make a hole, making it the cheapest kind
of plating too. However, this kind of PCB
requires more space. Plating through blind
hole This plating reduces the amount of space
used by the PCB with Plating Through Hole. Here,
the Via connects the external layer to one or
more inner layers of the PCB, and is responsible
for
2
the interconnection between the top layer and
inner layers. In this kind of plating, special
attention needs to be paid to the depth of the
hole. The process of blind hole plating is
difficult. Plating through buried hole This kind
of Via connects to any circuit layer of PCB, but
does not pass to the outer layer. This means
that only the inner layers of the board are
connected by the Via. It is buried inside the
board, and not visible from the outside thus the
name. This process of plating is not possible
using the method of bonding. Instead, individual
circuit layers need to be drilled, and then
bound together. Thus, this process requires more
time than other processes, which also makes it
very expensive. This kind of plating is used in
high-density circuit boards as it optimizes the
density of the boards without increasing the
board size or number of board layers
required. Stub Via In the stub Via, the through
portion starts from the top layer and ends at the
inner layer. The stub portion is the remaining
portion continuing from the inner layer junction
to the bottom layer. Another variation is the
through portion originating from one internal
signal layer, and terminating on another
internal signal layer. Here, there are two stubs
the first stub being from the first internal
layer junction to the top layer, and the second
stub being from the second internal layer
junction to the bottom layer. Back-drilled
Via This practice is executed on thick PCBs to
minimize stub length for bit-rates greater than
3Gb/s. The process removes the stub portion that
is otherwise the case in Plating Through Hole
Via. It is a post-fabrication drilling process
where the back-drilled hole is of a larger
diameter than the original Plating Through Hole.
This process can back-drill within 8 mils of the
signal layer to keep, so there will always be a
small stub portion attached to the Via. However,
there are drill bit size and tolerance issues
that come with back-drilled Vias.
Write a Comment
User Comments (0)
About PowerShow.com