Ping You Industrial Co.,Ltd
SMT Equipment Spare Parts Supplier&
PCB PCBA processing and production
|Place of Origin:||ShenZhen|
|Minimum Order Quantity:||1PCS|
|Packaging Details:||High quality carton packing, high quality vacuum packing,|
|Delivery Time:||5-10 work days|
|Payment Terms:||T/T, L/C, D/A, D/P, Western Union, MoneyGram|
|Supply Ability:||Ten thousand square meters per month|
|Color:||Green,brown||Number Of Plies:||6 Layer|
|Copper Thickness:||2oz||Base Material:||FR-4|
|Board Thickness:||1.4mm||Place Of Origin:||Guangdong, China (Mainland)|
94V0 PCB Printed Circuit Board,
1.4mm PCB Printed Circuit Board,
1.4mm 94V0 PCB
1.4mm 94V0 PCB Printed Circuit Board Electronic Ultrasonic Humidifier
|Base Material||fr-4||Ordinary Tg,|
|Board Thickness||Rigid PCB||0.6MM|
|Copper Thickness||inner layer||2 OZ|
|outer layer||2 OZ|
|Solder mask color||outer layer||Green|
|Character color||outer layer||white ,black, yellow|
|Min. Line Width||inner layer||0.05MM|
|Min. Line Spacing||inner layer||0.05MM|
|Drill Hole||Max Diling dameter||6.5MM|
|Min Diling Diameter||0.1mm|
|Drilig tolerance||PTH:+/-0.075mm NPTH:+/-0.05mm|
|Slot tolerance||PTH:+/-0.10mm NPTH:+/-0.05mm|
|Board Size||Rigid PCB||800*2000MM|
|Rigid -Flexible PCB||200*500MM|
|Drill Aspect Ratio||Mechanical hole||12.0:1.0|
|Solder mask bridge||green oil||0.08MM|
|Bow and Twist||Rigid PCB||0.5-0.75%|
|core thickness||Rigid PCB||0.075MM (excluding copper)|
|Resin plug hole||hole size||0.2-0.35mm|
|V - cut||Rigid PCB||30 45 60 (Tolerance: + / - 5 degrees)|
|impedance||50-120 ohm||Tolerance: + / - 10 %|
|PP type||Commonly used||1080,2116,7628 ,106|
Actual PCBA process steps.
Step 1: Soften the solder paste
The first step in PCB assembly is to apply solder paste to the board.The process is
similar to that of a silk-printed shirt, where a thin stainless steel template is
placed on the PCB in addition to the mask.This allows the assembler to apply solder
paste only to certain parts of the possible PCB.These parts are parts where the
components are placed in the finished PCB.
The solder paste itself is a gray substance made up of tiny metal balls, also known as
solder.The tiny metal spheres are made of 96.5% tin, 3% silver and 0.5% copper.The
solder paste is mixed with a solder flux, a chemical design that helps the solder melt
and bond to the surface.The solder paste, shown as grey solder paste, must be applied
in the right place and in the right amount to the circuit board.
In a professional PCBA production line, a mechanical fixture holds the PCB and
soldered formwork in place.The applicator then places the solder paste on the desired
area in a precise amount.The machine then spreads the paste across the template,
evenly across each open area.After the template is removed, the solder paste remains
in the desired position.
Step 2: Pick and place
After the solder paste is applied to the PCB board, the PCBA process moves to the
pickup and placement machine, and the robotic device places the surface-mount element
or SMD on the prepared PCB.Today, SMDs account for the majority of non-connector
components on PCB.These SMDs are then soldered onto the surface of the board in the
next step of the PCBA process.
Traditionally, this is a manual process done with a pair of tweezers, in which the
fitter must pick up and place the components by hand.These days, fortunately, this
step is an automated process between PCB manufacturers.This shift is largely because
machines tend to be more accurate and consistent than humans.While humans can work
quickly, fatigue and eye strain tend to set in a few hours after using these
gadgets.Machines work 24/7 without such fatigue.
The device initiates the pick-up and placement process by picking up a PCB board with
a vacuum clamp and moving it to a pick-up and placement station.The robot then locates
the PCB on the workstation and begins applying SMT to the PCB surface.These elements
are placed on top of the solder paste in the preprogrammed position.
Step 3: Reflow soldering
Once the solder paste and surface mount components are all in place, they need to be
left there.This means that the solder paste needs to solidify, attaching the
components to the circuit board.PCB assembly achieves this through a process called
After the pick-up and placement process is complete, it is transferred to a conveyor
belt.This conveyor belt moves through a large reflux oven, a bit like a commercial
pizza oven.The oven consists of a series of heaters that gradually heat the circuit
board to a temperature of about 250 degrees Celsius, or 480 degrees Fahrenheit.This is
hot enough to melt the solder in the solder paste.
After the solder is melted, the PCB continues to pass through the oven.It cools and
solidifies the molten solder in a controlled manner through a series of cooler
heaters.This creates a permanent solder joint that connects the SMD to the PCB.
Many PCBAs require special consideration during reflow, especially for two-sided PCB
assembly.The two-sided PCB assembly requires separate stencil printing and
reflow.First, the side of the less and smaller parts is stenciled, placed and reflux,
and then the other side.
Step 4: Inspection and quality control
Once the surface mount elements are soldered in place after the reflow process, this
does not complete the PCBA and requires functional testing of the assembled
board.Often, movement during reflow results in poor connection quality or no
connection at all.Shorts are also a common side effect of this movement, as misplaced
parts sometimes connect to parts of the circuit that should not be connected.
Checking for these errors and mismatches may involve one of several different
inspection methods.The most common tests include:
?Manual inspection: Despite the impending development of automation and intelligent
manufacturing, the PCB assembly process still requires manual inspection.For smaller
lots, on-site visual inspection by the designer is an effective way to ensure PCB
quality after the reflow process.However, as the number of plates being examined
increased, this method became increasingly impractical and inaccurate.Observing these
widgets for more than an hour can cause optical fatigue, leading to inaccurate
?Automatic optical inspection: for larger batches of PCBA, automatic optical
inspection is the more appropriate inspection method.The Automatic Optical Inspection
Machine, also known as AOI Machine, uses a series of high-power cameras to "see" the
PCB.These cameras are arranged at different angles to see the welded joints.Different
quality solder joints reflect light in different ways, allowing AOI to identify lower
quality solder.AOI does this at a very high speed, allowing it to process a large
number of PCBs in a relatively short period of time.
?X-rays: Another method of examination involves X-rays.This is a less common detection
method - it is most often used on more complex or layered PCB??.X-rays allow the
observer to see through the layers and visualize the lower layers to identify any
potential hidden problems.
The fate of the failure boards depends on PCBA's standards and they will be returned
for cleaning and reworking or scrapped.
Whether or not an inspection finds one of these errors, the next step in the process
is to test the part to make sure it does what it's supposed to do.This involves
testing the quality of the PCB connection.Boards that need to be programmed or
calibrated require more steps to test for correct functionality.
This check can be performed periodically after the reflow process to identify any
potential problems.These periodic inspections ensure that errors are found and fixed
as quickly as possible, which helps manufacturers and designers save time, manpower
Step 5: Insert the through-hole element
Depending on the type of board under the PCBA, the board may contain a variety of
components other than the regular SMD.These include electroplated through-hole
elements or PTH elements.
Plated through hole is a hole in the PCB that is always plated on the circuit
board.The PCB component uses these holes to pass signals from one side of the board to
the other.In this case, the solder paste will not be of any benefit, as the solder
paste will go straight through the hole with no opportunity for adhesion.
In the future PCB assembly process, PTH components do not need solder paste, but
require a more professional welding method:
?Manual welding: Manual through - hole insertion is a simple procedure.Typically, the
task of one person at a single station is to insert a component into the specified
PTH.When done, the circuit board will move to the next workstation while someone else
is plugging in another component.Each PTH that needs to be equipped will continue to
loop.This can be a lengthy process, depending on how many PTH components need to be
plugged in during one cycle of the PCBA.Most companies specifically try to avoid
designing with PTH components, but PTH components are still common in PCB design.
?Wave soldering: Wave soldering is an automated version of manual soldering, but
involves a very different process.After placing the PTH component in place, place the
board on another conveyor belt.This time, the conveyor belt passes through a special
oven, where a stream of molten solder is washed on the bottom of the circuit
board.This will immediately solder all the pins on the bottom of the board.For
double-sided PCBs, this welding is nearly impossible because welding the entire side
of the PCB would render any sophisticated electronic components unusable.
After this welding process is complete, the PCB can proceed to a final inspection, or
if the PCB needs to add additional parts or another side assembly, the previous step
can be performed.
Step 6: Final inspection and functional testing
After the welding step of the PCBA process is completed, the final inspection will
test the function of the PCB.This check is called a "functional test."This test allows
the PCB to complete its pacing, simulating the normal operation of the PCB.In this
test, power and analog signals pass through the PCB, while the tester monitors the
electrical characteristics of the PCB.
If any of these characteristics (including voltage, current, or signal output) show
unacceptable fluctuations or hit peaks outside the predetermined range, the PCB fails
the test.According to the company's standards, a failed PCB can be recycled or
Testing is the last and most important step in the PCB assembly process because it
determines the success or failure of the process.This testing is why it is so
important to test and inspect regularly throughout the assembly process.
After the PCBA
It is fair to say that the PCB assembly process can be a dirty one.The solder paste
leaves a certain amount of flux, and manual manipulation can transfer oil and dirt
from fingers and clothing to the PCB surface.Once all is done, the result looks a bit
bleak, which is both an aesthetic and a practical matter.
After a few months on the PCB, the flux residue starts to smell and feel sticky.It can
also become somewhat acidic, which can damage solder joints over time.In addition,
customer satisfaction is often affected when shipments of new PCBs are covered by
residues and fingerprints.For these reasons, it is important to clean the product
after all welding steps have been completed.
Stainless steel high pressure cleaning equipment using deionized water is the best
tool for removing residues from PCB.Washing the PCB in deionized water does not pose a
threat to the equipment.That's because the ions in regular water, not the water
itself, damage the circuits.Therefore, the deionized water is harmless to PCB as it
goes through the washing cycle.
After cleaning, a rapid drying cycle using compressed air makes the finished PCB ready
for packaging and transportation.
Provides the World′s Quickest - PCB Board Design to Loaded Assembly. If getting your design manufactured and to the marketplace first is critical to your success Pingyou Industrial is a great solution. No one beats our New Product Introduction (NPI) and New Product Development (NPD) capabilities. Zhongrun High-tech supports "ANY" or "ALL" of your PCB Board: Design, Layout, Bare Board Fabrication, Assembly, and Complete Box Build needs.
Pingyou Industrial offers the "World′s Quickest" service through our unique and dynamic capabilities. We control the entire process - Idea thru. Finish Product - and have the systems in place to seamlessly process from one step to another. This allows unparalleled cycle time reduction. Pingyou Industrial also eliminates the blame game, as we can handle it all.
Contact Person: PYPCB-Vera