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With the development of electronic technology and the upgrading of electronic products, electrical and electronic products reliability and safety of increasing demand, led to diverse and complex applications, circuit protection components has evolved into a many kinds of new electronic components field. Moreover, the global circuit protection device in 2000 reached 4.4 billion in sales. Demand-driven structure of the circuit protection components and technology are experiencing a rapid global change.
Technology trends and design challenges
--- To see the circuit protection components of the market outlook, we must understand the use of these electronic components, the future trend of the terminal market. These trends are: the growth of MDF applications; USB 2.0 and IEEE 1394 Plug and Play agreement to increase the acceptance rate; the concentration of end-use functionality and interoperability; of ESD increasing concern.
--- Looking at the electronic components market, we see growing demand is in a smaller footprint to provide the latest product features. For example, mobile phones and PDA, the urgent need to put more into a smaller user functionality within the device, resulting in a higher density printed circuit board (PCB). In order to meet the size limit and a smaller footprint to provide ESD (electrostatic discharge protection) protection, over voltage component manufacturers have developed a variable resistor 0402 and diode products. If the ESD event occurs, and no damage will stop, the light is soft failure (data loss), severe cases will cause permanent damage to the chip. The treatment of high-voltage ESD events (up to 15 000V) needs, many component manufacturers found themselves in the "extended" the current technical limitations encountered, can not further the size of their products smaller. Component manufacturers face the challenge of how to develop in a smaller package offers the same performance in different scenarios. Similar to the over-voltage protection challenge brought by board density, over-current applications, the device requires manufacturers to "reduce" their current products. Typically, over current products must meet the same flow with the previous products; This requires increasing the energy density of the device.
--- The next few years, the data protocol used today to drive the electronic circuit protection products in terms of speed significantly increased. This will dramatically change the evolution of board-level ESD protection market. In addition, in recent years, digital electronic products to the development of high-speed semiconductor devices and more and more low-voltage IC's work, have suffered greatly increased the chance of voltage and ESD hazards. Faced with this situation, there have been many over-voltage protection devices, such as TVS diodes, ceramic varistors, transient voltage suppressors, ESD suppressors. Some ESD protection IC manufacturers will design in the chip, able to create their own protective ESD, IC.
--- ESD protection usually depends on the variable resistor and diode technology progress. Both techniques provide excellent ESD protection, and with the low rate of data transmission lines compatible. For example, USB 1.1 runs at 12Mb speed data protocol; devices use the agreement to protect the microprocessor chip, a diode and variable resistor products make it from ESD damage. However, due to the capacitance of these devices is too high, the USB 2.0, IEEE 1394, or Infiniband device signal line can not be used, when the data rate increases, the signal line in order to maintain signal integrity, low capacitance ESD devices (less than 1pF) demand is also increasing. New polymer ESD suppression technology can provide a lower capacitance (less than 1pF), lower leakage current (low-power portable devices, which is particularly important), fast response time (<1ns) and low clamping voltage ( 100V), but also has the ability to withstand multiple ESD pulses, the structure can produce many different devices.
--- Resettable polymer (PTC) technology has been applied as a protective plug and play solution of choice. It is added in the organic conductive polymer particles formed, which is characterized by a self-recovery, ie, over-current and later returned to normal, do not change, do not have to be placed in electronic products it can reach areas in the hands , which brings many conveniences to the user. USB and IEEE 1394 as the growth in applications, circuit protection industry has on the use of resettable PTC products and packaging in 1206 and the previous-generation devices to achieve the same current at the ability to make a response. Reduction of this size requires a power density of the device increased by 300%. Industry will continuously meet the challenge, to change its design, and development aimed at demand trends, without sacrificing safety and reliability of polymer technology users need to over-current protection products. While this over-current protection devices there are some shortcomings, but its advantage is that since the restoration of the very attractive, the manufacturers have improved in the study, the main direction is to improve the breakdown voltage / current, reduce resistance, increase strength and stability.
--- In the electronic component market is one of the most difficult changes the convergence of electronic devices and connectivity, it raises many questions. For example, commercial and consumer electronics markets need to have digital cameras and Internet-enabled mobile phones, or they need a PDA-enabled mobile phones, then, the future role played by personal computer? Whether it can be with all other devices "sync up"? All devices on the market with "cradle" of capacity, mean that digital camera, PDA and mobile phone can synchronize with a personal computer? The answer remains unclear. Therefore, the electronic component manufacturers need to continue working because they will affect a wide range of product development and business strategy.
- When the electronic devices evolve to higher data rate protocols, the higher board density, more devices plug and play connectivity and more capacity, ESD protection on the overall demand will greatly increase. ESD Association believes that all electronic devices in the field about 30% of the fault is caused by ESD. Electronics engineers have a very clear understanding of this fact, but not with the reliability of these failures is becoming increasingly clear that the demand for ESD protection will greatly increase.
--- ESD "immune" is not only an international standard, it is also concerned about the end-product manufacturers an important guarantee of reliability. ESD protection is usually achieved through three techniques: multi-variable resistor, diode array and polymer suppressors. More products the market needs to deal with a wide range of ESD issues, and the need experts to design and test capabilities to ensure proper ESD protection.
Structural changes
--- Changes in circuit protection components is also reflected in the structure, which is a significant change from the traditional leaded surface mount components designed to change, especially to the evolution of multi-layer technology.
From leaded to surface mount
--- Number of passive components, including capacitors, resistors and inductors, surface mount years ago has turned to design. However, the electronic circuit protection devices, the majority of products are still lead type; However, to meet the needs of SMT, the use of surface-mount design of electronic circuit protection components certainly will appear in rapid growth.
--- On behalf of this variable resistor changes bear the brunt of the metal oxide variable resistor, and in the early 90s of last century achieved its component manufacturers or multi-layer stack design, increasing the products based on zinc oxide surge processing power. At that time, in the ultra-thin multi-layered technology components companies (mainly MLCC) began to apply the technology of zinc oxide, the production is very small, surface mount multi-layer designed to protect sensitive electronic equipment, so that from ESD. 1999 and 2000, multi-variable resistor in the cellular phone applications and automotive electronic components emerged rapidly.
--- This from the lead wire to the surface trend affect the installation of other ceramic components, especially ceramic NTC and PTC thermistors, so that toward the multi-layer design. However, the two products is still mainly used in the design of lead type, but they will soon be transformed into the surface of the installation. Gradually from the lead surface-mount design to the design of other products also rapidly changing electronic fuse, which uses ceramic matrix form, the interior contains a fusible metal element. Silicon-based circuit protection devices have begun to shift rapidly to the surface mount design. Now, zener diode, avalanche diode and crystal thyratron and all the traditional design also began to lead the rapid adoption of DO-214 plastic packages. SMD fuse for the development of high-end computers, telecommunications, data transmission system and an important key to IC provides over-current protection circuit.
Smaller, better, faster
--- In addition, the leaded and surface mount electronic circuit protection device to another trend is to make it more compact and effective. For example, in lead design, manufacturers are trying to make a variable resistor and thermistor smaller footprint and better clamping characteristics. Circuit protection devices leads to another trend is the glass passivation technology for a better moisture resistance. In the surface-mount design, manufacturers will continue to develop smaller, high-performance devices meet the EIA standards. Finally, the total board size will become smaller, while 0603,0402 and 0201 in the traditional package offers better features and faster clamping.
Array technology
--- The latest trend is similar and different circuit protection components to create multi-chip array. Market will provide the initial array of products including metal oxides and titanate ceramic-based products, because their production process is suitable for multi-chip array manufacturing process requirements. Multi-variable resistor manufacturer has produced multiple lines of protection and Octel Quad array prototype, especially for engine control I / O port components. It is expected that the current multi-chip array will be used for a variety of applications, which will ultimately affect the traditional fuse market, as well as PTC and NTC thermistor market. Array technology can make a printed circuit board, the density of circuit protection components multiply, so that the layout of components more easily, saving the OEM including the selection and installation costs, including the cost of using separate discrete components.
Integration
--- At present, the automotive electronic components have begun to use multi-variable resistors and multilayer capacitors. Other trends also include an integrated double-layer or multi-chip array design and the way to the variable resistor combined with a separate thermistor. Arrays may also be customized in a single package, while including a variety of circuit protection features to provide instant protection layer.
--- Also silicon-based integrated circuit protection devices had an impact. Use of more advanced semiconductor devices on silicon primary circuit protection features to achieve is possible. For example, in an integrated passive components (IPD) to create a functional addition to capacitance and resistance of the circuit other than the protective layer. IPD trends that have great significance, because many of these devices are installed on the computer and network connection device I / O port.
Demand for everything
--- We see the importance of circuit protection components become more and more. In all types of electronic products, set over-current protection and over voltage protection devices growing trend, the main driver from the following areas: IC functionality and integration is growing, and its value more and more expensive, need to strengthen protection; semiconductor components and more and more low-voltage IC's work in order to achieve lower power consumption, reduce heat and prolong the service life of purpose, the anti-over current / over voltage protection capacity needs to meet the new requirements; mobile phone, PDA , notebook computers, camcorders, digital cameras, CD-ROM and other mobile electronic products, more and more components need batteries as a power supply, the battery components and battery charger must be configured to protect the components; high-end electronics in your vehicle More and more equipment, and working conditions more than the average poor electronic products, electronic equipment necessary for the power adapter, in general, need to be installed over-current and over voltage protection components; in the electrical / electronic products, are needed to prevent lightning strikes and power line interference with the telephone line to pay in order to ensure proper communication and personal safety of users, over current / over-voltage protection devices demand rise; malfunction in the electronic products, 75% were due to too current / over-voltage caused by the failure of more computer power is due to 88.5% over current / over-voltage caused by the use must also be a large number of circuit protection components. It can be seen, over voltage, over current, thermal circuit protection components in the field of electronic components is a new growth point, has a good market and application.
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