PCBA Tech - How to select the chip inductor for PCB assembly?

Chip inductors, also known as surface mount inductors, are a modern type of leadless or short leaded miniature electronic components suitable for surface mount technology (SMT). The soldering surfaces of these inductors are on the same plane, making it easy to mount them on the printed circuit boards (PCBs) of various electronic devices.

Chip inductors are mainly used for storing and releasing energy. It converts electrical energy into magnetic energy or magnetic energy into electrical energy through the principle of electromagnetic induction. This makes it critical in a variety of applications such as filtering, regulating voltage and current, etc.

Selecting the right chip inductor requires consideration of a number of factors such as inductance, accuracy, power requirements, frequency range and size. By thoroughly evaluating these parameters, it is possible to ensure that the inductor adequately meets the needs of the circuit, thereby optimizing the performance and reliability of the electronic device. 

1.Inductance Selection

Inductance is one of the most important parameters of chip inductors, which directly affects the filtering and energy storage performance of the circuit. Select the appropriate inductance value according to the specific needs of the circuit design. If the inductance value is too low, the desired filtering effect may not be realized; while too high may lead to slower circuit response or cause unnecessary losses.

2.Precision and Tolerance

Chip inductors usually have an accuracy of ±10%, but for demanding applications, a higher accuracy, such as ±5% or lower, may be required. When selecting an inductor, an inductor with the appropriate tolerance should be chosen based on the accuracy requirements of the circuit. If the project has specific requirements for accuracy, it is recommended that the product be ordered in advance to ensure that the required accuracy can be obtained.

3.Power Requirements

Power tolerance is also a key factor when selecting inductors. Power consumption varies from circuit to circuit, so it is necessary to select the right inductor for the power requirements of the circuit. Too low power inductors may cause overheating or damage, affecting the overall stability of the circuit.

4.Frequency Range

The operating frequency range of chip inductors has a large impact on their performance. Common types include inductors for microwave high frequency applications and high frequency inductors for high power circuits. The inductor with the appropriate function should be selected according to the circuit operating frequency to obtain the best performance.

5.Size and Layout

Inductor size has a great impact on PCB design, especially in electronic devices with limited space. The appropriate size of chip inductor should be selected according to the PCB design and space constraints, while considering the impact of layout on heat dissipation and electrical performance to optimize the overall circuit design.

Main Advantages of Chip Inductors

1.Space saving

Chip inductors are designed with a planar structure, which allows for a more compact layout on the circuit board and helps save space. This design is particularly suitable for electronic devices with limited space, such as cell phones and portable devices.

2.Wide range of inductance

Chip inductors are available in a wide range of inductances, from millihenry (mH) to henry (H), to meet the needs of different circuits. In addition, the inductance value is highly accurate, and can stably provide the required inductance characteristics.

3.Low Loss

Compared to other types of inductors, chip inductors have low losses and a large quality factor (Q). This feature makes them superior in high frequency applications, effectively reducing signal attenuation and improving the overall performance of the circuit.

4.Simple manufacturing process

Chip inductors are relatively simple to manufacture, with short lead times and an abundant supply of raw materials. This reduces production costs and makes chip inductors competitive in the market.

5.High Power Carrying Capacity

Chip inductors usually have a large allowable current, which can be adapted to the requirements of high-power circuits, to ensure that the circuit works stably under high load conditions.

6.Lightweight

Due to their thin chip structure, chip inductors are lightweight and suitable for use in weight-sensitive applications such as aerospace and portable devices.

7.Closed Magnetic Circuit

Chip inductors are designed with a closed magnetic circuit to avoid interference with surrounding components and are less susceptible to electromagnetic interference from neighboring components, which facilitates high-density component mounting.

Chip inductor can be categorized into four main types:wirewound,stacked,braided and film chip inductor.

1.Wirewound Inductors

A wirewound inductor is a miniaturized version of the traditional wirewound inductor.They are manufactured by winding wire around an insulating substrate and are typically used where higher power or a specific inductance value is required.The advantages of this type of inductor are its simplicity and low manufacturing cost, making it suitable for mass production.

2. Stacked Inductors

Stacked inductors are made using multi-layer printing technology and stacked production process.These inductors are relatively small in size, have better high frequency characteristics and lower DC resistance,and are suitable for space-constrained electronic products.Stacked inductors are widely used in all kinds of power supply and signal processing circuits because of their stable performance.

3.Braided Inductors

Braided inductors are usually made by interleaving multiple wires and are suitable for high-frequency applications.Their structure helps to reduce the inductor's electromagnetic interference (EMI),so they have their own unique advantages in certain specific circuit designs.

4. Thin Film Inductors

Thin film inductors are manufactured through thin film technology and offer a higher degree of integration and smaller size.Its superior high-frequency performance makes it suitable for use in high-frequency applications, especially in modern electronic devices that require high-efficiency layout.

Chip inductor plays a key role in PCB design,and their type,function and design considerations are critical to the performance of electronic devices. As technology and applications continue to advance, the importance of inductors will grow.By accurately understanding and applying inductors, designers can improve the efficiency and stability of circuits, opening up more innovative possibilities.