According to the specific requirements of product assembly and assembly equipment conditions to choose the right means of assembly, is the basis of high efficiency and low cost of assembly production, too
A, SMT assembly way of the first kind is mixed single mixed assembly, namely SMC/SMD and hole instrumentation components (
Conventional distribution on one side of the PCB is different, but the welding surface is only single.
This way of assembly adopts single sided PCB and wave soldering (
Now generally adopts double wave soldering)
There are two kinds of process, the specific assembly way (
The first assembly style known as the first method, namely the PCB surface (B
Mount SMC/SMD first, and then the a-side instrumentation THC.
After the method.
Stick method after the second mode of assembly is called, is first in A PCB surface instrumentation THC, B side after SMT SMD.
Second, SMT two-sided assembly way the second type is double mix assembly, SMC/SMD and T.
HC can be mixed in with the side of the PCB, at the same time, the SMC/SMD may also be distributed in.
Double sided PCB.
Double mixed assembly using double-sided PCB, double wave soldering or reflow soldering.
In the way of assembly also has to post of SMC/SMD or after the difference, generally according to the size of the type of SMC/SMD and PCB reasonable choice, usually USES the first method is more.
The commonly used two kinds of assembly assembly way.
SMC/SMD and 'FHC ipsilateral way, SMC/SMD with THC.
On one side of the PCB.
SMC/SMD and different modes of lateral iFHC, assemble the surface integrated chip (
And THC on the PCB of A surface, but the SMC and small outline transistor (
On the B side.
This kind of assembly due to the way in which the single side or double side PCB SMT SMC/SMD, and inserted the surface has a lead of assembly components hard to assemble, so very high density assembly.
Three, the whole surface assembly way all mean surface mount on the PCB only SMC/SMD and no THC.
The current components has not been fully implemented in SMT, the assembly in the actual application form.
This kind of PCB assembly method is generally in the thin line graphics or ceramic substrate, using fine pitch components and reflow welding process for assembly.
It also has two assembly method: (
Methods: single surface mount single-sided PCB in a single assembly SMC/SMD.
Double surface assembly way: using double-sided PCB assemble at two sides, SMC/SMD, higher density assembly.
SMT processing and assembly process mainly depends on the surface of the assembly of components,
Type, use the types of components and assembly equipment conditions.
Generally SMA can be divided into single-sided, double-sided pack 2 mixed assemble and the whole surface on a total of 6 three types of assembly way.
Different types of SMA the assembly method is different, the same kinds of SMA the assembly method can also be different.
SMT technology now is widely used in electronics factory, the main development and progress towards four directions.
One is adapted to new type of surface mount components assembly requirements;
2 it is adapted to the development of the new assembly materials;
Three is the variety and modern electronic products, updating fast characteristics match;
Four is with high density assembly, 3 d assembly, mems assembly, and other forms of the new assembly assembly requirements.
With the fine pitch components pin, 0.
3 mm pin spacing of micro assembly technology has tend to mature, SMT processing technology is to improve the quality of assembly and a passing direction assembly;
As the device at the bottom of the array, the popularity of ball pin form, with the corresponding assembly process and test, repair technology has been maturing, continues to improve at the same time;
In order to adapt to the development of green assembly and lead-free welding new assembly materials after put into use, such as assembly process requirements, related technology research is under way;
In order to adapt to many varieties, small batch production and product assembly requirements of quick update, rapid restructuring technology assembly process, assembly process optimization technology, assembly design * * integration technology are put forward and the ongoing studies;
In order to adapt to high density assembly, 3 d assembly assembly process technology, is the main content to research on a period of time;
Want to install strict bearing, precision demands special assembly such as the surface of the assembly process technology, and for a period of time need to study the content, such as the surface of the mechanical and electrical system assembly, etc.
Turn-key Electronics Manufacturing Services for Printed Circuit Boards and Assembly