Aturan Dasar Tata Letak dan Pengkabelan Komponen

Ada beberapa aturan dasar yang harus diikuti ketika mendesain tata letak. Aturan-aturan ini termasuk menjaga bidang daya dan ground di dalam papan, menghindari cross-netting, dan menempatkan komponen yang paling penting terlebih dahulu. Anda juga harus mencoba menempatkan IC dan prosesor besar di dalam papan. Dengan mengikuti aturan-aturan ini, Anda tidak akan mengalami kesulitan dalam mendesain dan membuat papan sirkuit.

Hindari menyeberangi jaring

Ketika menyambungkan komponen-komponen, Anda harus menghindari jaring-jaring yang bersilangan. Jika ada vias, pastikan jaraknya cukup jauh untuk menghindari persilangan. Cara lain untuk menghindari persilangan jaring adalah dengan menempatkan pin positif satu IC di depan pin negatif IC lainnya. Dengan cara ini, Anda akan menghindari persilangan jaring pada PCB.

Tempatkan prosesor dan IC berukuran besar di dalam board Anda

Mikroprosesor, IC, dan komponen elektronik besar lainnya adalah jantung dari sebagian besar sirkuit. Mereka ada di mana-mana dan dapat ditemukan di hampir setiap papan sirkuit. Mereka dapat berupa perangkat sederhana dengan hanya beberapa transistor atau perangkat kompleks dengan jutaan atau bahkan miliaran transistor. Ada banyak jenis IC yang tersedia, termasuk mikrokontroler 8-bit, mikroprosesor 64-bit, dan paket lanjutan.

Hindari menempatkan vias pada bidang daya dan tanah

Menempatkan vias pada bidang daya dan arde akan menciptakan rongga, yang dapat menimbulkan titik panas di sirkuit. Untuk alasan ini, yang terbaik adalah menjauhkan jalur sinyal dari bidang-bidang ini. Aturan umum yang umum adalah menempatkan vias dengan jarak 15 mil. Selain itu, ketika menempatkan jalur sinyal, pastikan ada 1350 tikungan per via.

Dalam sistem distribusi daya PCB yang khas, bidang daya dan arde terletak pada lapisan luar. Lapisan ini dicirikan oleh induktansi rendah dan kapasitansi tinggi. Pada sistem digital berkecepatan tinggi, noise pengalihan dapat terjadi. Untuk mengurangi hal ini, gunakan bantalan pelepas panas untuk membuat sambungan listrik.

Hindari menempatkan vias pada jejak

Apabila memasang kabel komponen, penting untuk menghindari menempatkan vias pada jejak. Vias adalah lubang yang dibor pada papan yang dilalui kabel tembaga tipis dan disolder pada kedua sisinya. Idealnya, vias harus ditempatkan setidaknya seperdelapan panjang gelombang dari jalur. Praktik ini akan menurunkan suhu operasi IC dan membuat desain lebih dapat diandalkan.

Vias sangat berguna dalam memindahkan sinyal dari satu lapisan ke lapisan lainnya. Tidak seperti jejak yang berjalan dari satu lapisan ke lapisan lainnya, vias juga mudah diidentifikasi jika ada perubahan desain yang diperlukan. Vias adalah jack-of-all-trade dari tata letak PCB, yang menyediakan konektivitas listrik antar lapisan. Selain itu, mereka berfungsi sebagai alat yang efektif dalam mentransfer panas dari satu sisi papan ke sisi lainnya.

3 Penyebab dan Penanggulangan Teratas Kekurangan Pasta Solder dalam Desain PCB

Ada beberapa penyebab dan penanggulangan kekurangan pasta solder dalam desain PCB. Ini termasuk sambungan solder yang dingin, penempatan yang tidak akurat, terlalu banyak panas selama penyolderan, dan kebocoran bahan kimia. Berikut adalah beberapa penyebab yang paling umum dan cara mengatasinya.

Sambungan solder dingin

Untuk menghindari pembentukan sambungan solder dingin, perancang PCB harus mendesain PCB sedemikian rupa sehingga semua komponen ditempatkan pada orientasi yang sama dan memiliki jejak komponen yang baik. Hal ini membantu menghindari masalah ketidakseimbangan termal dan asimetri pada sambungan solder. Selain itu, penting juga untuk mendesain PCB sedemikian rupa sehingga setiap komponen diposisikan pada pad berbentuk D. Juga penting untuk menghindari penggunaan komponen yang tinggi karena komponen tersebut menciptakan zona dingin dalam desain PCB. Selain itu, komponen di dekat tepi papan lebih mungkin menjadi lebih panas daripada komponen di bagian tengah.

Sambungan solder yang rusak dapat disebabkan oleh berbagai faktor, termasuk kurangnya fluks atau sambungan yang tidak terikat dengan baik. Area kerja yang bersih sangat penting untuk kualitas sambungan solder yang baik. Penting juga untuk melapisi ulang ujung solder untuk mencegah oksidasi.

Kebocoran bahan kimia

Jika Anda seorang perancang PCB, Anda mungkin tertarik untuk mempelajari cara menghindari kebocoran bahan kimia. Masalah ini disebabkan oleh bola solder, yang muncul sebagai bola kecil solder yang menempel pada permukaan laminasi, penahan, atau konduktor PCB. Karena panas yang dihasilkan, kelembapan di dekat lubang tembus dalam PCB dapat berubah menjadi uap dan mengeluarkan solder.

Solder bridging adalah masalah lain yang disebabkan oleh kekurangan pasta solder. Ketika solder tidak dapat terpisah dari timah sebelum mengeras, maka akan membentuk korsleting. Meskipun korsleting sering kali tidak terlihat, namun hal ini dapat menimbulkan kerusakan pada komponen. Beberapa faktor dapat menyebabkan masalah ini, termasuk jumlah pin pada PCB, jarak di antara mereka, dan pengaturan oven reflow. Dalam beberapa kasus, perubahan bahan juga dapat menyebabkan penghubung solder.

Terlalu banyak panas selama penyolderan

Pasta solder dapat rentan terhadap perubahan bentuk ketika mencapai suhu tertentu selama penyolderan. Terlalu banyak panas selama penyolderan dapat menyebabkan bola solder dan perubahan bentuk. Pasta solder yang terlalu banyak juga dapat menyebabkan fluks yang keluar terlalu banyak. Faktor-faktor ini dapat menyebabkan bola solder dan cacat pada desain PCB.

Pasta solder tidak boleh berinteraksi dengan kelembapan atau kelembaban. Masker solder harus diposisikan dengan benar dan bagian bawah stensil harus dibersihkan secara teratur. Kesalahan desain PCB umum lainnya dikenal sebagai efek batu nisan, atau "efek Manhattan", yang disebabkan oleh ketidakseimbangan gaya selama penyolderan. Efek ini menyerupai bentuk batu nisan di pemakaman. Namun, ini merupakan desain PCB yang tidak berfungsi dengan sirkuit terbuka.

Membersihkan material dengan benar setelah pengeboran

Kekurangan pasta solder adalah hasil dari bahan yang tidak dibersihkan dengan benar setelah pengeboran. Kawat solder harus berada pada suhu yang tepat dan idealnya dibasahi sepenuhnya dengan bantalan dan pin. Jika solder tidak dibasahi secara memadai, hal ini dapat menyebabkan pembentukan jembatan solder atau cacat lainnya. Jumlah solder yang tepat diperlukan untuk membasahi bantalan dan pin secara merata. Jika tidak, maka dapat membentuk lapisan oksida logam pada objek yang direkatkan. Hal ini dapat diperbaiki dengan membersihkan bahan dengan baik dan menggunakan besi solder yang tepat.

Insufficient solder can cause several problems with the circuit board. Inadequate solder can cause a sand hole, broken line, “blow hole” or “solder joint void.” Insufficient solder paste can also lead to the removal of tin from components. It’s essential to avoid such problems by following the PCB design process.

Preventive measures

Solder bridging occurs when solder gets into a space it shouldn’t. Solder bridging can be prevented by using larger component leads. When pads are too small, the solder has to wet a larger area and flow a smaller volume up the lead. This results in solder balls that form and cause shorts. It is important to place pads at optimal positions and use proper solder paste in the soldering process.

A lack of solder paste on the board can also cause component leads to be warmer than pads because component leads have less thermal mass and a higher flow of air around them. Increasing the soak time of solder paste will prevent this issue and equalize temperatures across the assembly. It also reduces the tendency for solder to flow towards warmer surfaces. Another prevention method is to optimize the stencil design to minimize the amount of solder paste on trouble areas. In addition to using a stencil, ensuring that the components are not damaged before placement can help reduce solder paste in problematic areas. Copper balancing can also be used to even out the heating and cooling of the PCB.

How to Do ESD Protection During SMT Assembly

Electrostatic damage is a major cause of device failure. It is responsible for causing direct failures in as much as 10% of electronic devices. It can cause problems throughout the SMT assembly process. Fortunately, there are ways to protect yourself from this problem.

Static protective material

It is imperative to protect electronic components from electrostatic discharge (ESD), which can lead to damage and failure. Static electricity can be generated at any time or place, and is often caused by friction. It is important to protect electronic devices during the SMT assembly process, so they can maintain optimum performance and reliability. Static protective material should be used from the beginning of the assembly process, and should be continued after completion.

The RH of the manufacturing environment also plays a vital role in the generation of ESD, so the factory’s RH should be carefully controlled. If the RH is not maintained correctly, it can result in very high levels of ESD. It is also recommended to keep materials with high levels of static electricity away from the assembly line. To protect your electronics from ESD, you should use static protective material during the assembly process.

ESD suppression components

To prevent damage from ESD during the SMT assembly process, the components should be stored and transported in ESD-proof bags. Professional assemblers are highly recommended for such work.

To prevent static electricity, assembly employees should wear anti-static clothing. They should also avoid touching the components with sharp objects. Anti-static clothing can also act as a grounding circuit for electronic devices. In addition to wearing conductive clothing, assembly personnel should wear a protective suit and shoes to reduce the risk of static electricity. It is also important to minimize the use of insulating materials.

Static electricity can occur because of metal components, which conduct an electrostatic charge. It can also be caused by induction or body static. The effects can be harmful, particularly to electronic components.

Static protective foam

Electrostatic discharge (ESD) can cause costly damage to electronics. While there are ways to prevent this, it is not possible to shield every device from the effects of ESD. Fortunately, anti-static foams, also known as electrostatic discharge foams, are available to protect sensitive components.

To minimize the risks associated with ESD, use protective packaging for electronic components. Make sure that the packaging is made of appropriate surface and volume resistivity. It should also resist triboelectric charging effects from movement during transit. Typically, electrostatic sensitive components are supplied in black conductive foam or an anti-static bag. Anti-static bags contain partially-conductive plastic that acts as a Faraday cage.

Static electricity is a common problem during the SMT assembly process. It is a byproduct of friction and can cause components to fail. Human movement generates static electricity that can range from a few hundred volts to several thousand volts. This damage can affect electronic components resulting from SMT assembly and can result in premature failure.

ESD bags

When working with electronics, it is important to use ESD protective packaging when transporting and storing susceptible items. ESD protection can help minimize the risk of electrical shocks and burns, while also providing transport and storage protection. A protective package can also protect the parts and components while they are not in use, such as when they are being transported to and from the factory.

While handling a PCB, it is important to follow the manufacturer’s instructions and follow their guidelines. This is essential because a poor ESD protection plan can result in damage to electronic components. If you are unsure of how to properly handle the components during the assembly process, ask a professional.

Combination of both

To avoid static electricity during SMT assembly, it is essential to ground the electronics. Grounding can be of two types, soft grounding and hard grounding. Soft grounding means connecting the electronic devices to a low-impedance ground, while hard grounding means connecting the electronic components to a high-impedance ground. Both types of grounding can prevent static electricity and protect electronic components from damage.

ESD is a major source of damage in the electronics industry. ESD causes performance degradation and even component failure. It’s estimated that 8% to 33% of all electronics failures are caused by ESD. Controlling this type of damage can improve efficiency, quality, and profits.

Menganalisis Peran Desain Tumpukan Berlapis dalam Menekan EMI

Layered stack design is the process of using a PCB with many layers to improve signal integrity and reduce EMI. A general purpose high-performance 6-layer board, for example, lays the first and sixth layers as ground and power layers. In between these two layers is a centered double microstrip signal line layer that provides excellent EMI suppression. However, this design has its disadvantages, including the fact that the trace layer is only two layers thick. The conventional six-layer board has short outer traces that can reduce EMI.

Impedance analysis tool

If you’re looking for a PCB design tool to minimize your PCB’s susceptibility to EMI, you’ve come to the right place. Impedance analysis software helps you determine the correct materials for your PCB and determine which configuration is most likely to suppress EMI. These tools also allow you to design your PCB’s layered stack in a way that minimizes the effects of EMI.

When it comes to PCB layered stack design, EMI is often a major concern for many manufacturers. To reduce this problem, you can use a PCB layered stack design with a three to six-mil separation between adjacent layers. This design technique can help you minimize common-mode EMI.

Arrangement of plane and signal layers

When designing a PCB, it is vital to consider the arrangement of plane and signal layers. This can help to minimize the effect of EMI. Generally, signal layers should be located adjacent to power and ground planes. This allows for better thermal management. The signal layer’s conductors can dissipate heat through active or passive cooling. Similarly, multiple planes and layers help to suppress EMI by minimizing the number of direct paths between signal layers and power and ground planes.

One of the most popular PCB layered stack designs is the six-layer PCB stackup. This design provides shielding for low-speed traces and is ideal for orthogonal or dual-band signal routing. Ideally, higher-speed analog or digital signals should be routed on the outer layers.

Impedance matching

PCB layered stack design can be a valuable tool in suppressing EMI. The layered structure offers good field containment and set of planes. The layered structure allows for low-impedance connections to GND directly, eliminating the need for vias. It also allows higher layer counts.

One of the most critical aspects of PCB design is impedance matching. Impedance matching allows the PCB traces to match the substrate material, thus keeping the signal strength within the required range. Signal integrity is increasingly important as switching speeds increase. This is one of the reasons why printed circuit boards can no longer be treated as point-to-point connections. Since the signals are moving along traces, the impedance can change significantly, reflecting the signal back to its source.

When designing PCB layered stacks, it is important to consider the inductance of the power supply. High copper resistance on the power supply increases the likelihood of differential mode EMI. By minimizing this problem, it is possible to design circuits that have fewer signal lines and shorter trace lengths.

Controlled impedance routing

In the design of electronic circuits, controlled impedance routing is an important consideration. Controlled impedance routing can be achieved by using a layered stack up strategy. In a layered stack up design, a single power plane is used to carry the supply current instead of multiple power planes. This design has several advantages. One of these is that it can help avoid EMI.

Controlled impedance routing is an important design element for suppressing EMI. Using planes separated by three to six mils can help contain magnetic and electric fields. Furthermore, this type of design can help lower common-mode EMI.

Protection of sensitive traces

Layered stack design is a critical element in suppressing EMI. A good board stack-up can achieve good field containment and provide a good set of planes. But, it must be designed carefully to avoid causing EMC problems.

Generally, a 3 to 6-mil separated plane can suppress high-end harmonics, low transients, and common-mode EMI. However, this approach is not suitable for suppressing EMI caused by low-frequency noises. A three to six-mil-spaced stack up can only suppress EMI if the plane spacing is equal to or greater than the trace width.

A high-performance general-purpose six-layer board design lays the first and sixth layers as the ground. The third and fourth layers take the power supply. In between, a centered double microstrip signal line layer is laid. This design provides excellent EMI suppression. However, the disadvantage of this design is that the trace layer is only two layers thick. Therefore, the conventional six-layer board is preferred.

How to Understand Some Important Steps in the Design of PCB Boards

If you are interested in designing a PCB board, there are a number of important steps that you must know. These steps include Ideation, Definition, Validation, and Placement of components. Understanding these steps will help you make the best design possible.

Ideation

Creating an effective PCB board design starts with defining the purpose of the device. It is essential to match the board’s dimensions and height constraints with the intended components. Other considerations include the components’ ESR at high frequencies and temperature stability. In addition, it is necessary to choose the proper trace width and spacing. Failure to adhere to this general rule can lead to an explosion of costs.

The PCB design process begins with ideation, definition, and validation. This step is critical and occurs before designing a prototype or executing a design. It highlights the designer’s creativity and makes sure that all hardware components are aligned and congruent. It also enables cross-collaboration among the various team members, resulting in synergy.

Definition

The design of a PCB is a complex process. It includes choosing the right materials for the PCB base, selecting a design rule, and selecting the final dimensions. The PCB must also be tested to ensure that it will function properly under the intended operating conditions. If the design is not done correctly, the project could end in failure.

The first step in PCB design is to create a set of blueprints. This is done through computer software. The blueprints serve as a model for the design. The designer can also use a trace width calculator to determine the inner and outer layers. The conductive copper traces and circuits are marked in black ink. The traces are known as layers in the PCB design. There are two types of layers, the outer and the inner.

Validation

PCB boards go through validation processes to ensure they are designed correctly. These tests are performed by examining the board’s structures. These structures include probes and connectors, as well as the Beatty standard for material parameters. These tests are performed in order to eliminate any design errors, such as reflections.

The PCB boards are then prepared for manufacturing. The process depends on the CAD tool used and the manufacturing facility. It usually involves the generation of Gerber files, which are drawings of each layer. There are several Gerber viewer and verification tools available, some of which are built into CAD tools, while others are standalone applications. One example is ViewMate, which is free to download and use.

The validation process also involves testing the device. The design is tested with a prototype to ensure it meets the expected response. In addition, it includes an analysis of the circuit to determine if the design is stable. The results of this test determine if any changes are required. Some modifications should be made in order to improve the design and ensure that it meets the specifications of the customer.

Placement of components

Placement of components on PCB boards can be done in many ways. You can place them above or below another component, or you can use a combination of these methods. Placements can be made tidy by aligning components by choosing Align Top or Align Bottom. You can also evenly distribute components on the board by selecting components and right-clicking on them. You can also move components to the top or bottom side of the PCB by pressing L.

When designing PCBs, placement of components is crucial. Ideally, components are placed on the top side of the board. However, if the component has a low thermal dissipation, then it can be placed on the bottom side. It is also recommended to group similar components together and place them in an even row. Moreover, you should also place decoupling capacitors in close proximity to active components. In addition, you should place connectors according to the design requirements.

Dielectric breakdown voltage

Whether you’re designing your own PCB or sourcing a PCB from a manufacturer, there are several steps that you should know about. Some of these steps include: testing the PCB’s electrical components and layout for functionality. This is done by running it through a battery of tests in accordance with IPC-9252 standards. Two of the most common tests are isolation and circuit continuity tests. These tests check whether there are any disconnections or shorts in the board.

After the design process is complete, it’s important to consider the thermal expansion and thermal resistance of the components. These two areas are important because the thermal expansion of the board components increases when it gets hotter. The Tg of a board’s components must be high enough to prevent the components from being damaged or deformed. If Tg is too low, it can cause the components to fail prematurely.