PCB Assembly

The COVID-19 pandemic has had a major global impact, both in scale and severity. A large-scale influenza is raging around the world, and even developed countries cannot control it. No one knows when this epidemic will end, but one thing is certain, that is, the new crown epidemic has promoted the medical electronics market.

Looking back at the epidemic in the past few years, the medical electronics market has been in a bull market with little fluctuation, showing a non-stop growth market. As you know, the demand for ventilators in the medical industry has exploded since the COVID-19 pandemic began to impact the global healthcare system. In 2019, the global demand for ventilators was only 77,000 units, but in April 2020, the demand in New York City alone reached 33,000 units. The same feature also includes forehead thermometers, which are hard to come by even after prices soared in the first few months of 2020. This series of time represents that the medical electronics industry is on the cusp, and even related electronic products can develop very well, such as: medical PCB (electronic components), medical plastic products, medical testing equipment, etc.

But in fact these sudden revenues did not make manufacturers happy, which largely affected the local supply chain, resulting in price confusion and lower profit margins as a result. Such unsustainable growth can suddenly collapse like a fall off a cliff. No company will welcome it or survive. For various reasons, we do not want the big market to be overwhelmed by short-term market fluctuations, but pay more attention to the long-term development of the medical electronics market.

Basic electronic medical facilities

From this incident, we should clearly realize that the medical system in the world today is relatively fragile. In addition to the capabilities of the medical industry itself, the supply capacity of its downstream manufacturers is also insufficient. When the whole world is eagerly waiting for medical supplies, PCB manufacturers cannot provide large quantities of PCBA to medical electronics manufacturers in a short time. At present, there are many PCBA companies in operation, but there are very few PCBA companies that meet the needs of medical PCB manufacturing and assembly. In addition to this example, there are many examples of insufficient downstream supply. We need to learn from these lessons and think about how to improve the medical electronics industry, whether it is downstream or upstream.

The most immediate impact on medical facilities is the development of cutting-edge medical equipment, which requires a government push. For example, the defibrillator is a kind of heart emergency equipment. Due to insufficient manufacturing capacity and insufficient promotion and research and development, people's recognition of it is not high. For this reason, the government needs to strictly implement manufacturing specifications and increase the promotion of high-density interconnection technology for PCB manufacturers.

The management of medical resources requires not only the addition and updating of hardware, but also the enhancement of "software". Huge growth opportunities exist in the use of technology to digitize healthcare resource management. For example, the use of RFID tags commonly used to manage surgical equipment can be extended to the management of medical equipment. Companies are already exploring ways to use NFC tags to manage critical resources such as medicines and vaccines to gather data and gain insights. As far as the "data" value chain is concerned, there are many "opportunities" from data detection, transmission to processing.

Accelerate the transformation of the operating model

The impact of the new crown on the medical industry is only reflected in the field of basic medical electronics, or it is a problem with the entire operating model. Traditional electronic medical manufacturers need to start manufacturing from the source, that is to say, they need to carry out PCB manufacturing, assembly, testing, finished product assembly, sales and other links. This model has obvious limitations, one of which is the small effective area, which is the most serious loophole in the new crown epidemic, and it is also the core problem that medical products cannot be supplied in time.

In order to solve this problem, the medical industry urgently needs more suppliers who provide medical PCBA services to build a new medical system. The PCBA service provider is responsible for the link of electronic components, the electronics manufacturer serves the finished product manufacturing link, and the seller serves the sale of medical electronics to the government and medical institutions. The core idea of this new operating model is to use IoT technology to deliver medical resources to patients faster. This can better achieve long-distance coverage, instant feedback, and efficient diagnosis and treatment.

New operating models have also spawned new products and solutions. More and more portable consumer medical devices such as blood pressure monitors, blood glucose meters, ECG monitors, and ultrasound scanners are entering people's lives, replacing (or supplementing) traditional professional medical equipment (increasing).

The radio frequency circuit is the RF circuit, which refers to the radio frequency current, which is the abbreviation of a high-frequency alternating electromagnetic wave. When the alternating current of the circuit changes less than 1000 times per second, it is called low-frequency current, and when it is greater than 1000 times, it is called high-frequency current, and radio frequency refers to high-frequency current.

A radio frequency circuit refers to a circuit in which the electromagnetic wavelength of the processing signal is on the same order of magnitude as the circuit or device size. At this time, due to the relationship between the size of the electronic device and the size of the wire, the circuit needs to be processed with the relevant theory of distribution parameters. This type of circuit can be considered as a radio frequency circuit, and there is no strict requirement for its frequency, such as the AC transmission line for long-distance transmission (50Hz Or 60Hz) Sometimes it is also dealt with by the relevant theory of RF.

Next, FS PCBA takes the mobile phone RF circuit as an example to introduce the principle of the RF circuit in detail.

The structure and working principle of the radio frequency receiving circuit:

When the mobile phone is receiving the signal, the antenna converts the electromagnetic wave sent by the base station into a weak alternating current signal. After filtering and high-frequency amplification, it is sent to the intermediate frequency for demodulation, and the received baseband information (RXI-P, RXI-N, RXQ-P, RXQ-N) is obtained, which is sent to the logic audio circuit for further processing.

Circuit Analysis - Circuit Structure:

The receiving circuit is composed of antenna, antenna switch, filter, high-amplification tube (low noise amplifier), intermediate frequency integrated block (receiving demodulator) and other circuits. Early mobile phones had primary and secondary mixing circuits, the purpose of which was to lower the receiving frequency before demodulation.

The structure and working principle of the transmitting circuit

When transmitting, the transmitting baseband information processed by the logic circuit is modulated into the transmitting intermediate frequency, and the frequency of the transmitting intermediate frequency signal is changed to 890M-915M (GSM) frequency signal by TX-VCO. After being amplified by the power amplifier, it is converted into electromagnetic waves by the antenna and radiated out.

Circuit Analysis - Circuit Structure:

The transmission circuit is composed of transmission modulator, transmission phase detector, transmission voltage-controlled oscillator (TX-VCO), power amplifier (power amplifier), power controller (power control), transmission transformer and other circuits inside the intermediate frequency.

The structure and working principle of the local oscillator circuit (local oscillator circuit, phase-locked loop circuit, frequency synthesis circuit)

The circuit generates four sections of local oscillator frequency signals (GSM-RX, GSM-TX, DCS-RX, DCS-TX) without any information, and sends them to the IF. The baseband information is modulated and transmitted phase-detected.

Circuit Analysis - Circuit Structure: There are four circuit pcb assembly structures in the mobile phone local oscillator circuit:

a) Composed of frequency synthesis integrated block, receiving voltage-controlled oscillator (RX-VCO), 13M reference clock, and preset frequency reference data (SYN-DAT, SYN-CLK, SYN-RST, SIN-EN)

b) Integrate the frequency synthesis integrated block inside the intermediate frequency, combined with an external RX-VCO (multi-purpose for mid-term phones and Nokia phones)

c) Integrate the frequency synthesis integrated block and the receiving voltage-controlled oscillator (RX-VCO), called the local oscillator integrated block (multi-purpose for mid-term and Samsung phones)

d) Integrate the frequency synthesis integrated block and the receiving voltage-controlled oscillator (RX-VCO) inside the intermediate frequency (multi-use for new models and miscellaneous brands).

It is worth noting that no matter what kind of structural mode is adopted, only the generated frequency is different, and its working principle, direction and function of the generated frequency signal are the same.

Application of radio frequency circuit

RF technology is widely used in many fields, such as: TV, radio, mobile phone, radar, automatic identification system, etc. The term RFID (radio frequency identification) refers to the application of radio frequency identification signals to identify objects. RFID applications include:

1. ETC (Electronic Toll Collection)

2. Railway rolling stock identification and tracking

3. Container identification

4. Identification, authentication and tracking of valuables

5. Object management for commercial retail, healthcare, logistics services, etc.

6. Access control management

Expensive and complex discrete interconnect cables can reduce design reliability, increase design cost and overall design size. In practice, discrete interconnect cables are a disadvantageous design. For electronic product sellers it goes against the trend of miniaturization of electronic products, and for PCBA manufacturers, it is an unreliable design. For project leaders, discrete interconnect cables are not only more expensive but also more complex. Fortunately, FS Technology's rigid-flex PCBA will be the perfect substitute.

The advantages of FS technology manufacturing rigid-flex PCB

FS Technology specializes in the production of this rigid-flex PCBA, which is designed for flexibility and reliability to provide a cost-effective and convenient solution for your electronic projects. Discrete interconnects have different conductor orientations, whereas flex PCBAs keep all conductors in a specific orientation fixed to each other. Accurate modeling and more predictable design of PCBA traces with reliability and flexibility.

In addition, in the part of the FPC, FS Technology provides gold finger contacts, allowing the edge of the FPC to be used as the male part of the connector and can be adapted to high-density designs. Today, in order to meet the needs of electronic product users, this rigid-flex PCB replaces almost all traditional discrete interconnect solutions and enables a highly modular design.

The benefits of rigid-flex PCBA for electronic projects

FS Technology's flexible PCBA not only provides an effective method for designing and producing interconnect solutions, but also enhances the accommodation of the circuit board and becomes the focus of the solution. The use of rigid-flex PCB can make the volume of electronic products smaller, which is unmatched by traditional circuit boards. Instead of mounting components to rigid PCBs, you can mount boards produced by FS Technologies on all flexible solutions. In addition to the above advantages, the rigid part of the rigid-flex PCBA can act as a stiffener, providing your electronic project with a reliability that a flexible PCB cannot. Most of the wearable devices, digital cameras, and medical devices used today use rigid-flex PCBs instead of just FPC or rigid PCBAs.

FS Technology believes that flexible rigid PCB is the best of all flexibility solutions. Features a flex-rigid design with built-in interconnect between the two boards. Using rigid-flex PCBAs manufactured by FS Technology in different solutions, designers can accommodate 3D solutions in one assembly step. The use of rigid-flex PCBA instead of traditional circuit boards or discrete connections can shorten the assembly time of mechanical assembly. As the demand for PCBs by electronic product sellers increases, it is proved that rigid-flex PCBs are a catalyst for any electronic solution.

Although rigid-flex PCBs are better than traditional PCBs, they are very similar in the design process. As a turnkey PCB manufacturer, special attention to mechanical quality is required when creating flexible parts. When creating a 2D layout of a flexible PCB design, it is best to use a 3D modeling software to create a mockup of the flexible design, or to create a paper mockup of the design. This method is convenient for testing whether the design meets the mechanical specifications of the flexible substrate. In addition to that, the PCB you design does not need to have a bend radius smaller than what a flex PCB allows.

FS Technology recommends that you pay attention to the following points when designing rigid-flex PCBs:

Increase board flexibility with staggered traces on each layer of the flex circuit.

Conductors must not be routed perpendicular to the bend radius

Termination areas should be reinforced with stiffeners

Use a cross-hatched pattern instead of a solid plane

Vias should be kept away from bend areas

Communication with turnkey rigid-flex PCB assembly company

Before sending manufacturing files of rigid-flex PCB to FS Technology, please consider the plan's executable in advance, such as the flex board is bendable and has the highest density when nested. If a specific dimension can be achieved by bending the PCB, usually we do not bend it in the initial design, but in the assembly step. Finally, I hope you know that the few rigid-flex PCBAs you design are more expensive than flexible PCBs. Try to use a smaller number of layers for your project needs, it will be more profitable for the electronics you sell. Flexible rigid solutions should only be considered if your design has very large layer count requirements.

Finally, filling a flex PCB is very similar to filling a rigid PCB. When doing flexible PCB assembly, consider the following tips:

Bake the flex PCBs for an hour, then fill them to remove any absorbed moisture.

Fix the flex PCB to a hard surface to provide dimensional stability when soldered to the device.

When hand-soldering the device to the flex PCB, skip the solder-intensive fixtures to avoid overheating parts of the flex PCB.

With the progress of China's manufacturing capacity, the PCBA industry has also ushered in a climax. In this article, FS Technology will explain to you what technologies Chinese PCBA assembly companies use in assembly.

What is PCB Assembly Process

As we all know, the operation of electronic products is inseparable from the printed circuit board, and PCB is its abbreviation. A PCBA board is assembled from a bare PCB board and electronic components. The bare board refers to the green board, and the electronic components are the objects soldered to the bare board. The bare board cannot function alone. The PCB manufacturing company draws the wiring on the bare board, and the electronic components are electrically connected according to the wiring to function. It can be said that the PCB board is a carrier, and the electronic components are the main body. More differences between PCB and PCBA can be found in FS Technology's blog post PCB vs PCBA .

The PCB assembly process refers to the process in which a turnkey PCB assembly company places components on a bare board through a series of assembly techniques. Generally, surface mount technology or packaging technology is used. That is SMT process and DIP. A qualified turnkey PCB assembly company has the most advanced and professional assembly machines that can work 24 hours a day.

Specific PCBA assembly process

FS Technology provides customized versions, that is, to manufacture suitable PCBA boards according to customer needs. Therefore, we will use different processes according to the size, number of layers, materials, and required functions of the circuit board. What are the pcba processing and assembly processes?FS Technology divides it into the following categories：

Single Side Mount

Single Side Mixed

Double Sided Mounting

Double-sided mixed

Single-sided mounting process

The single-sided mounting process is one of the simplest processes. Generally, the electronic components of this PCB assembly company are mounted components (SMD). FS Technology only needs to stick these components on one side of the pcb board.The specific process is as follows：

Incoming Inspection

Print

Patch

Reflow Soldering

Cleaning

Detect

Single-sided mixing process

Single-side mixing is more difficult than single-side mounting, but even so, most PCB assembly companies can complete the job. The single-sided mixing process refers to mounting different types of PCB components on one side of the bare board, and the components used include mounting and plug-in. The specific process flow is as follows:

Incoming

Detect

Print

Patch

Reflow Soldering

Cleaning

Plugin

Wave Soldering

Cleaning

Detect

Double Sided Mounting Process

The double-sided mounting process means that the components are all mounted components, and the components are mounted on both sides of the PCB board, commonly known as double-sided PCB boards.The specific mounting process is as follows:

Incoming Inspection

A side printing of pcb board

Patch

Reflow Soldering

Flip

PCB board B side printing

Patch

Reflow Soldering

Cleaning

Detect

Double-sided mixing process

The double-sided mixing process refers to components that are both mounted and plug-in, and components are mounted on both sides of the pcb board. This process is very difficult, and few turnkey PCB assembly companies in China can complete it. The specific process is as follows:

Incoming Inspection

A side printing of pcb board

Patch

Reflow Soldering

PCB board B side plug-in

Lead bend

Flip

B-side point patch glue

Patch

Drying

Flip

Wave Soldering

Cleaning

Detect

Abstract: Design a printed circuit board based on a schematic circuit to perform the functions required by the circuit manufacturer. Print design design refers to the circuit design, which must take into account the external design of the joint, the detailed design of the internal electrical components, and the detailed design of the metal joints and holes. What are the PCB circuit board design software? FS Technology will introduce you the mainstream pbc circuit board design software

The most popular circuit board design software in China

Protel, protel 99se, protel DXP, Altium are widely used in China. All of this software is developed and continuously developed by the company; the current version, Altium Design 15, is straightforward and can be used to easily create FS Tech PCB boards. But these softwares are not suitable for making hard PCBs.

Design better circuit board design software

Cadence SPB software Cadence SPB is Cadence software, the latest version is Cadence SPB 16.5; ORCAD design program is a global standard, and is also the most used circuit board design software by FS Technology; PCB design and simulation are more complete, and the use is much more complicated than Protel. The requirements and features are complex; but the rules are designed for the design, so the design is better, less work, and significantly stronger than the prototype.

Circuit board design software that few people use

Metor Boards and EEs, which only work on BOARDSTATION UNIX systems, are not designed for PCs, so they are rarely used; the current MentorEE version is Mentor EE 7.9, Cadence SPB is the same standard as PCB design software, and in some respects is better than Cadence Poor SPB. FS Technology has hardly used this type of board design software

The most popular circuit board design software in Europe and America

Many people do not know much about the maintenance of circuit boards. Next, FS Technology will explain the maintenance skills of PCBs.

1. Observation method

When we receive an FS Tech PCB for repair, we first take a closer look at what it looks like. If the PCB is burnt, please confirm that the power supply PCB is normal before turning on the PCB, and then turn it on again to ensure that no secondary damage will be caused. The observation method is a static verification method, when using the observation method, the following steps are usually followed.

Step 1: Check whether the PCB is artificially damaged;

Step 2: Check whether the PCB components are burned out;

Step 3: Test the integrated circuits in the PCB;

Step 4: Check the chain for loose, burnt or damaged caterpillars. It is a copper hole that sinks from the platform;

Step 5: Check the fuses (including fuses and thermistors) in the FS Technology PCB to make sure the fuses are not blown. Sometimes the fuse is too thin to see, and auxiliary equipment such as a multimeter can be used to determine whether the fuse is damaged.

2. Fixed measurement method

For most printed circuit boards, previous methods of observation do not detect problems. Although a small number of PCBs may be physically deformed for some reason, the cause of the failure is not difficult to determine. point on the graph. Methods of measuring, identifying and solving problems.

Before measuring, first determine whether the circuit is controlled by an analog or digital signal. The following are just standard methods for measuring digital circuits, and management basically follows the steps below.

Step 1: Use a multimeter to check whether there is a short circuit between the power supply and the ground;

Step 2: Measure the diode with a multimeter and check that it is working properly;

Step 3: Use a resistance multimeter to measure the capacitance to see if it is a short circuit or an open circuit. If there is, it means that there is a problem with this part of the FS technology circuit. The unit or circuit associated with it. ;

Step 4: Measure integrated circuits, transistors, resistors, etc. with a multimeter. In the PCB, see if they match their own logic characteristics

Tips and Warnings Most PCB management issues can be resolved by reviewing both observational and static measurement methods. Remember that the power supply must be normal, so as not to damage the secondary circuit after the next step.

3. Network measurement method

PCB wiring is a key factor in ESD protection, FS Technology believes that a reasonable PCB design can reduce unnecessary costs caused by fault inspection and rework. In PCB design, it is more important to overcome the electromagnetic interference (EMI) electromagnetic field effect generated by the discharge current, because the transient voltage suppression stopper (TVS) diode is used to suppress the direct charge injection caused by the ESD discharge.

This article will provide optimized ESD protection for PCB design criteria.

1. Circuit loop.

When current enters circuit loops by induction, these loops are closed and have variable magnetic flux. The current range is proportional to the area of ​​the ring. Larger loops contain more magnetic flux and therefore have stronger current induction in the circuit. Therefore, the loop area must be reduced. The most common loop consists of power and ground wires.

Multilayer PCB designs employ power and ground planes, where possible. Multilayer circuit boards not only minimize the circuit area between power and ground, but also reduce the high-frequency EMI electromagnetic fields generated by ESD pulses. If multilayer boards were not possible, FS Technology would have to connect the circuits for the power and ground lines into a grid. The grid connection can play the role of power and ground, and the printed lines of each layer should pass through holes and the connection interval in each direction should be within 6 cm. In addition, when wiring, the power and ground printed lines produced by FS Technology are as close as possible, which can also reduce the loop area.

Another way to reduce loop area and induced current is to reduce parallel paths between interconnects. When a signal cable longer than 30 cm must be used, a protective wire can be used. A better approach is to place the ground near the signal lines. The signal line should be within 13mm of the protection line or grounding line. Arrange long signal wires (>30cm) or power wires and their ground wires of each sensitive element in a crossover. Crossovers must be separated from top to bottom or left to right.

2. The length of the circuit connection.

Long signal lines can also be used as antennas for receiving ESD pulse energy. Trying to use short signal lines can reduce the efficiency of antennas receiving ESD electromagnetic fields. In order to reduce the printed line length of the interconnection, FS Technology will try to place the interconnection equipment in the adjacent position.

3. Inject the ground charge.

1. The PCB must have a Mark point corresponding to the positioning of the entire board on the diagonal of the long side of the board.

Chips with an IC pin center distance of less than 0.65mm on FS Technology’s circuit boards should have a Mark point corresponding to the chip positioning on the diagonal of the long side of the IC; when there are patches on both sides of the pcb, both sides of the pcb should be Add Mark points based on this article.

2. The edge of the PCB should retain the 5mm process edge (the minimum spacing requirement for the machine to clamp the PCB).

Chips whose center-to-center distance between IC pins is less than 0.65mm should be greater than 13mm from the edge of the board (including the edge of the process); the four corners of the board should be chamfered with a φ5 arc. Judging from the current bending degree of PCB wings, the optimal splicing length is about 200mm (equipment processing size: maximum length is 330mm; maximum width is 250mm), try not to spell in the width direction to prevent bending during production.

3. MARK point functions and categories.

Mark points, also known as fiducials, provide a common measurable point for all steps in the assembly process to ensure that each assembly device can accurately locate the circuit pattern. Therefore, FS Technology believes that the Mark point is crucial for SMT production.

4. MARK point design specification recommended by our department.

1) Shape: It is recommended to mark the Mark point as a diameter: R=1.0mm solid circle; 2) Form a complete MARK point, including marked points (or feature points) and open areas. 3) Position: The Mark point is located at the relative position of the diagonal on the veneer or puzzle, and is separated as much as possible; it is best to distribute it at the longest diagonal position (such as the MARK point position diagram). 4) In order to ensure the installation accuracy requirements of FS Technology, SMT requirements: each PCB must have at least one pair of MARK points for the SMT machine to identify, and there must be a single-board MARK (when assembling). Panel MARK or combined MARK only play a role of auxiliary positioning. 5) When assembling, the relative positions of the MARK points of each single board must be the same. The position of the MARK point cannot be moved for any reason, resulting in asymmetrical position of the MARK point of each board; 6) All MARK points on the PCB are only valid: two MARKs appearing in pairs on the same diagonal are valid. So MARK points must appear in pairs to be used (MARK point location map).

7) The distance between the MARK point (edge ​​of the open area) and the edge of the PCB must be ≥5.0mm (minimum spacing requirements for the machine to clamp the PCB)

8) Requirements for open areas.

Around the mark point marking, there must be an open area with no other circuit features or markings. The radius of the circle in the open area is R≥2R, where R is the radius of the MARK point. When R reaches 3R, the machine recognition effect is better.

9) PBC Materials

Mark point markings can be bare copper, which is protected by a transparent anti-oxidant coating. If solder mask (solder mask) is used, the mark point or its open area should not be covered.

10) PBC Contrast.

On a PCB with a patch, in order to locate the entire PCB, it is usually necessary to place the optical positioning points on the four corners of the PCB, generally three.

Common reference points mainly include three types of board reference points, unit reference points and local reference points.

1. Reference point structure

(1) Panel datum point and unit datum point.

Shape/Size: 40mil diameter solid circle. FS Technology Solder Mask Window: A circle concentric with the reference point, the size is twice the diameter of the reference point. A 2mm diameter edge requires a round or octagonal copper wire as a guard ring. The internal background of the optical positioning reference symbols on the same board should be the same, that is, whether there is copper foil under the three reference symbols should be consistent.

(2) Local datum point.

Parts such as QFP and pitch ≤0.4mm BGA, CSP, FC need to place local fiducials. Size/Shape: Solid circle, 40mil diameter. Solder mask opening: The size is processed according to the ordinary pad, and the outer ring copper ring cannot.

2. Place the datum point:

General principles:

The veneer for processing SMT equipment must be placed with fiducial points. The number of single-sided reference points is greater than or equal to 3. For single-sided layout, simply place the datum point on the component face. ..When A5I5^0L-z1m+PPCB is double-sided layout, the fiducials are placed on both sides. For the datum points placed on both sides, except for mirror splicing, the positions of the datum points on both sides are basically the same.

(1) The reference point for FS Technology to place the puzzle.

Panel datum points and cell datum points need to be placed. There are three panel fiducials and unit fiducials. The edges of the board are distributed in an L shape, and keep them as far away as possible. Figure A below shows the location requirements for the panel datum points. When using a mirror-symmetrical panel, the reference point on the auxiliary side must meet the requirements of overlapping after flipping, as shown in Figure B below.

(2) The datum point for placing the cell board.

1. The PCB must have a Mark point corresponding to the positioning of the entire board on the diagonal of the long side of the board.

Chips with an IC pin center distance of less than 0.65mm on FS Technology’s circuit boards should have a Mark point corresponding to the chip positioning on the diagonal of the long side of the IC; when there are patches on both sides of the pcb, both sides of the pcb should be Add Mark points based on this article.

2. The edge of the PCB should retain the 5mm process edge (the minimum spacing requirement for the machine to clamp the PCB).

Chips whose center-to-center distance between IC pins is less than 0.65mm should be greater than 13mm from the edge of the board (including the edge of the process); the four corners of the board should be chamfered with a φ5 arc. Judging from the current bending degree of PCB wings, the optimal splicing length is about 200mm (equipment processing size: maximum length is 330mm; maximum width is 250mm), try not to spell in the width direction to prevent bending during production.

3. MARK point functions and categories.

Mark points, also known as fiducials, provide a common measurable point for all steps in the assembly process to ensure that each assembly device can accurately locate the circuit pattern. Therefore, FS Technology believes that the Mark point is crucial for SMT production.

4. MARK point design specification recommended by our department.

1) Shape: It is recommended to mark the Mark point as a diameter: R=1.0mm solid circle; 2) Form a complete MARK point, including marked points (or feature points) and open areas. 3) Position: The Mark point is located at the relative position of the diagonal on the veneer or puzzle, and is separated as much as possible; it is best to distribute it at the longest diagonal position (such as the MARK point position diagram). 4) In order to ensure the installation accuracy requirements of FS Technology, SMT requirements: each PCB must have at least one pair of MARK points for the SMT machine to identify, and there must be a single-board MARK (when assembling). Panel MARK or combined MARK only play a role of auxiliary positioning. 5) When assembling, the relative positions of the MARK points of each single board must be the same. The position of the MARK point cannot be moved for any reason, resulting in asymmetrical position of the MARK point of each board; 6) All MARK points on the PCB are only valid: two MARKs appearing in pairs on the same diagonal are valid. So MARK points must appear in pairs to be used (MARK point location map).

7) The distance between the MARK point (edge ​​of the open area) and the edge of the PCB must be ≥5.0mm (minimum spacing requirements for the machine to clamp the PCB)

8) Requirements for open areas.

Around the mark point marking, there must be an open area with no other circuit features or markings. The radius of the circle in the open area is R≥2R, where R is the radius of the MARK point. When R reaches 3R, the machine recognition effect is better.

9) PBC Materials

Mark point markings can be bare copper, which is protected by a transparent anti-oxidant coating. If solder mask (solder mask) is used, the mark point or its open area should not be covered.

10) PBC Contrast.

PCB (Printed Circuit Board) is an important electronic component of electronic components, a support body and an electrical connection carrier for electronic components. It is called a "printed" circuit board because it is made of electronic printing. Before the advent of printed circuit boards, the interconnection between electronic components depended on the direct connection of wires to form a complete circuit. Now, the circuit breadboard is just an effective experimental tool, and the printed circuit board of FS Technology has become the absolute dominance of the electronics industry.

At the beginning of the 20th century, in order to simplify the production of electronic machines, reduce the wiring between electronic parts, and reduce production costs, people began to study the method of replacing wiring with FS technology printed circuit boards.

For the past 30 years, engineers have proposed using metal conductors for wiring on insulating substrates. The most successful is.

In 1925, Charlesducas in the United States printed circuit patterns on insulating substrates, and then successfully established a conductor as wiring by electroplating.

Until 1936, the Austrian Paul Eisler (Paulesler) released foil technology in the United Kingdom, he used a printed circuit board in a radio equipment; in Japan, Miyamoto Kisuke successfully applied for a patent, using spraying and wiring. Methods, Methods of Explosion and Wiring (Patent No. 119384).

Of the two approaches, Paulesler's approach is most similar to today's printed circuit boards. This method is called the subtraction method, which is to remove unnecessary metal; and Charlesducas, Miyamoto Kisuke's method is to add only the required wiring, which is called the addition method.

Nonetheless, due to the high heat of electronic parts at the time, the substrates of the two were difficult to use together, so there was no formal practical work, but it also brought printed circuit technology a step further.

In 1941, the United States painted copper paste on talc for wiring to make proximity tubes.

In 1943, Americans used the technology extensively in military radios.

In 1947, epoxy resins began to be used for manufacturing substrates. At the same time, NBS began to study manufacturing technologies such as coils, capacitors, and resistors formed by printed circuit technology.

In 1948, the United States officially recognized the invention for commercial use. Since the 1950s, FS Technology's lower calorific transistors have largely replaced the status of vacuum tubes, and printed circuit board technology has only begun to be widely used. At that time, etched foil technology was the mainstream.

In 1950, Japan used silver paint for wiring on glass substrate and copper foil for wiring on paper phenolic substrate (CCL) made of phenolic resin.

In 1951, with the advent of polyimide, the heat resistance of resin was further improved, and polyimide substrates were also produced.

In 1953, Motorola developed a double-sided plated through-hole method. This method is also applied to later multi-layer circuit boards. Printed circuit boards are widely used in the 1900s, and their technology is becoming more and more mature. Since the introduction of Motorola's double-sided board, multilayer printed circuit boards have begun to appear, making the ratio of wiring to substrate area even higher.

In 1960, V. Dahlgreen made a flexible printed circuit board by sticking a metal foil film with a printed circuit in a thermoplastic plastic.

In 1961, the Hazeltine Corporation in the United States referred to the electroplating through-hole method to produce a multi-layer board.

In 1967, "Plated-up technology", one of the layer-up methods, was published.

In 1969, FS Technology's FD-R made flexible printed circuit boards with polyimide.

In 1979, Pactel published the "Pactel method", one of the build-up methods.

In 1984, NTT developed the "Copper Polyimide method" for thin film circuits.

In 1988, Siemens developed the Microwiring Substrate build-up printed circuit board.

In 1990, IBM developed the "Surface Laminar Circuit" (Surface Laminar Circuit, SLC) build-up printed circuit board.

In 1995, Panasonic developed the ALIVH build-up printed circuit board.

In 1996, Toshiba developed Bit's build-up printed circuit board. Just in the late 1990s when many build-up printed circuit board solutions were proposed, build-up printed circuit boards have also been officially put into practice in large numbers until now.

The one-stop service for PCBA circuit board assembly is the good news for customers, that is, customers package their own requirements for circuit board assembly, hand over all the materials to FS Technology, and FS Technology directly assembles the finished product and sends it to the customer, including "assembly and detection". Customers only need to accept the goods after receiving the goods.

What exactly does FS Technology's one-stop service include?

FS Technology's one-stop PCBA assembly service includes PCB design, PCB proofing, PCBA processing (including SMT, DIP), connector crimping, BGA soldering, rework, reballing, PCBA testing,turnkey printed circuit board assembly, packaging and delivery.

FS Technology is customer-centric and thinks about PCBA services from the perspective of customers. Customers only need to put forward requirements, solutions and final product sales. It is the principle of FS Technology to let customers devote themselves to the research and development and sales of new products, and save a lot of time, energy and production costs for customers.

Different from traditional circuit board manufacturing

According to the traditional method, due to the insufficient ability of electronic product manufacturers, they often find professional PCB manufacturers to make circuit boards, and DIP or SMT manufacturers to make patches, and finally assemble, test and sell the products themselves after acceptance. This traditional approach will cost customers more money and time.