Circuit board machining line spacing is small

The circuit protectiondevice is divided into overvoltage type and overcurrent type according to the different protection effects. Traditional overcurrent protection is generally the application of fuses, but because of its disadvantages are obvious, can only play a protective role, therefore, in Shuokai Electronics reusable PTC self-recovery fuse research and development after the successful mass production, in many overcurrent protection applications instead of fuses, especially outdoor communication, security equipment overcurrent protection, Almost all of them are PTC self-restoring fuses. The following are the main points and points for attention in selection of PTC self-restoring fuses of overcurrent devices arranged by Shuokai Electronics:

Key points of selection of PTC self-restoring fuse:

1. Keep the current slightly higher than the user's normal working current.

2.Vmax must be greater than or equal to the user's large operating voltage.

3.Imax should be larger than the short-circuit current of major faults.

PTC self-restoring fuse selection points for attention:

1.PPTC is actually a positive temperature coefficient thermistor, so it is greatly affected by temperature. The parameters in the specification are measured at around 25℃. As the temperature increases, the holding current and trigger current will decrease, so it is important to know the temperature of the environment in which PPTC is applied.

2.PPTC is used to prevent back-end equipment from short-circuiting and abnormal current, and cannot be used to prevent transient surge, because its operation time is relatively slow.

3. The operation time of PPTC is controlled by the short-circuit current. The larger the short-circuit current is, the faster the operation time will be.

The overvoltage device is divided into clamp type and switch type according to the different mode of action. Switching type overvoltage devices are the lightning protection devices we are familiar with: ceramic gas discharge tube, semiconductor discharge tube and glass discharge tube. Another class of clamp type overvoltage devices are clamp type overvoltage devices with transient suppression diode, varistor, patch varistor and ESD discharge diode.

The following four points should be noted in the selection of overvoltage protection devices:

1) Selection of turn-off voltage Vrwm. Generally, the turn-off voltage should be at least 10% higher than the line high working voltage;

2) Clamp voltage VC selection. VC refers to the voltage passed by TVS in ESD impact state, it is less than the protected circuit can withstand the large transient voltage;

3) The selection of surge power Pppm. The protection time varies with the power, such as 600w (10/1000μs); 300W (8/20μs);

4) Selection of intermediate capacitance. The higher the operating frequency of protected components, the smaller the capacitance of TVS is required.

Data shows that the total amount of  data continues to grow and is expected to reach 40ZB(equivalent to 4 trillion GB) in 2020; Data security threats continue to rise, driving the demand for data security products * growth, ** data security has become a topic of increasing concern in various industries. In the ICCAD2019 conference held recently, Dr. Jiang Tianyi, CEO of Zhixiang Technology, shared his experience and experience on how to use new technologies such as big data analysis and the best data such as the intellectual property rights of IC design enterprises to establish the best security system.

"Zhixiang technology to help integrated circuit enterprises protect data code security, IP security as the main goal. It protects against both external intrusion and internal leakage, such as preventing incidents like Snowden." Jiang Tianyi pointed out in an interview, "We chose this field because we think data security is becoming more and more important for enterprises, and a lot of data leakage will cause losses to enterprises. And domestic enterprises in recent years to this aspect of the awareness of prevention is also gradually enhanced, the market prospects are promising. This is the original intention of Zhixiang Technology in this market."

Perhaps related to the chip design industry, Jiang Tianyi * put the market entry point on the data security protection of IC design enterprises. "In the current increasingly fierce competition in the industry and the industry development pressure, for IC design enterprises, IP intellectual property, research and development and other data is the enterprise's most competitive advantage." Jiang Tianyi said.

And IC design enterprise data protection has its own special needs. In the past, IC design enterprises should take physical protection as the main security scheme, try to meet the security needs by superimposing security products and security functions, but often bring weak coordination, various mechanisms incompatible problems. Not only is it difficult to effectively protect critical data, but it also has a significant impact on R&D, office experience and productivity.

At the same time, manual auditing makes it difficult to trace security incidents and sensitive projects fail to meet safety compliance requirements. These security problems have become an obstacle to the development of integrated circuit design enterprises and even the whole industry. Therefore, the IC industry needs the most effective security technology and products to cope with the security challenges brought by the industrial state.

"The IC industry is unique. Different from traditional data protection, each aspect of IC design has different security requirements. In view of these needs, Zhixiang technology has done targeted design. That's the main reason why our business is growing so fast in the IC industry." Jiang Tianyi said.

It is understood that Zhixiang technology launched based on the concept of "no boundaries" integrated circuit industry security solutions, for R & D, office, outsourcing and other scenarios, will be deployed between the enterprise server and terminal to an shield products as a unified business and research and development operations, centralized management and control of enterprise key data assets. At present, the scheme has been widely used in Spreadtrum, Whole Zhi, Junzheng and other domestic IC design enterprises.