PCB News - PCBA Substitution Processing Cost Analysis

PCBA Substitution Processing Cost Analysis
In the last article, we introduced how to choose the right PCBA processing factory! In addition to choosing the most cost-effective foundry to control costs and ensure quality, where should we proceed to further reduce costs and increase profit margins?

Let's start with the basis of PCBA. PCB is a printed circuit board, an important electronic component, and a carrier of electronic components. Because it is made by electronic printing, it is usually called a "printed" circuit board.

Then PCBA is a PCB with assembled components. The current assembly component technology is generally divided into two types, SMT patch and THT plug-in technology, which is called "DIP plug-in" in the industry. In fact, this statement is not very professional, because DIP is just One of the component packages used in THT plug-in technology. SMT is currently the most popular technology and process in the electronics assembly industry.

Surface Mount Technology (SMT)

It is a kind of surface mount components (SMC/SMD for short, chip components in Chinese) that are packaged in a matrix arrangement without leads or short leads or balls, mounted on the surface of a Printed Circuit Board (PCB) or Circuit assembly technology in which the surface of other substrates is soldered and assembled by methods such as reflow soldering or dip soldering.

Through Hole Insertion Technology (THT)

Through hole plug-in technology English full name Through Hole Technology, abbreviation: THT. Through hole technology is to insert components on the circuit board, and then use solder to solder firmly.

So what is the difference between SMT and THT?

Features of SMT

1. SMT finished PCBA (Printed Circuit Board Assembly), with high assembly density, small size and light weight: The volume and weight of SMD components are only about 1/10 of the traditional THT through-hole plug-in components. After adopting SMT, the volume of electronic products is reduced. 40%-60%, weight reduction 60%-80%;

2. The PCBA quality performance of SMT soldering is stable: the solder joints are firm and reliable, the anti-vibration ability is strong, and the solder joint defect rate is low;

3, PCBA soldered by SMT has stable electrical properties and low energy consumption: short parts and wiring, fast transmission and low energy consumption, reduced electromagnetic and radio frequency interference, and stable and reliable high-frequency characteristics;

4, SMT is easy to automate, improve production efficiency, save materials, energy, equipment, manpower, time, and reduce costs by 30%-50%.

The difference between SMT and THT

SMT is developed from traditional THT, but it is different from traditional THT. From the perspective of assembly process technology, the fundamental difference between SMT and THT is "sticking" and "inserting". The difference between the two is also reflected in the substrate, All aspects of components, component shapes, solder joint shapes and assembly process methods.

On the traditional THT printed circuit board, the components and solder joints are located on both sides of the board; while on the SMT circuit board, the solder joints and components are on the same side of the board. Therefore, on the SMT printed circuit board, the through holes are only used to connect the wires PTH on both sides of the circuit board, the number of holes is much smaller, and the diameter of the holes is much smaller. In this way, the assembly density of the circuit board can be greatly improved.

SMT has advantages over THT. Can THT technology be completely abandoned?

In the field of consumer electronics, most of the SMT has been achieved, but in electronic products such as automobiles and industrial control, there are not so clear requirements for space, and the components or modules with excessive current are still limited by space. The use of THT process is still More frequent. For now, SMT cannot completely replace THT for the time being.

SMT cost analysis

Since I know that SMT has advantages and low cost compared with THT. So let's analyze the processing cost of SMT.

Materials: solder paste, flux, glue, cleaning agent, etc.;

Working hours: PCB layout, number of patches, etc.;

Manpower: SMT does not require many people, about 3-4 people per line;

Equipment: The investment depends on the complexity of the product, which requires electricity and inert gas;

Others: The workshop needs to be anti-static, install air-conditioning, exhaust air, etc.;

The cost of proofing processing is: points * unit price of one point + solder paste, AOI inspection cost + download calibration cost + combined board cutting cost + steel mesh cost.

As for the cost of a PCBA proofing, the above has been more clear. The foundry of SMT is definitely much cheaper than the cost of THT plug-in assembly. SMT technology can be used as much as possible in SMT mounting technology., Billing by points + steel mesh + solder paste fee + download calibration + cutting board fee is a very classic algorithm. I hope it will help you to choose the foundry and calculate the cost.