Circuit protection, power control, and sensors are the three major development directions of Littelfuse

More than 80 years ago, Littelfuse started out as a small fuse. Today, its products are no longer limited to this. A large number of unique circuit protection application product portfolios have expanded Littelfuse's product line, including TVS diodes (transient suppression diodes), varistors, SIDACtor devices, PulseGuard ESD suppressors, GDTs, PTCs and SPAs (semiconductor protection arrays), etc. They cover the application markets of various industries and provide very flexible options for electronic manufacturers to design circuit protection.

Recently, Littelfuse Global Technical Marketing Manager Du Zhide said in an interview with reporters that it is precisely because of years of persistence and continuous innovation in high-performance circuit protection solutions that Littelfuse ranks first in the global circuit protection field and has a strong customer base of approximately 150,000.

In the field of circuit protection, Littelfuse's product line is almost the broadest, mainly including four major series: overvoltage protection, overcurrent protection, power monitoring and leakage protection relays, power control and distribution. Among them, fuses and TVS diodes are Littelfuse's main protection products, which are used to protect semiconductor components from damage by high voltage transients. The TVS diode PN junction has a larger cross-sectional area than the PN junction of an ordinary diode, so it can ground large currents without being damaged. The AK series TVS diode is dedicated to protecting valuable and important equipment, such as telecommunications infrastructure equipment, industrial transient voltage surge suppression systems (TVSS), railway track signal control rooms, defense and avionics equipment, and power grids and transmission systems. Compared with traditional solutions, it has a longer life, lower protection voltage, and smaller size. For example, it can be used in base stations to replace the original large and bulky lightning protection modules, thereby saving space and improving system performance.

Du Zhide said that for all electronic products and electrical equipment, safety is always the first priority. As the functions of electronic products increase and the systems become increasingly complex, the importance of circuit protection is gradually becoming apparent. Protection solutions must keep up with the trend of circuit design to ensure the reliability and high performance of the system. For popular applications such as Ethernet, USB3.0, LED lighting, LTE, wind power, and solar energy in recent years, Littelfuse has launched related products and has been widely recognized by the market.

Littelfuse TVS diode arrays provide Ethernet port protection against four main threats: lightning-induced surges, electrostatic discharge (ESD), electrical fast transients (EFT), and cable discharge events (CDE).

As the data transmission rate of USB3.0 rises to 5Gbps, the power drawn from USB increases, and the ESD electrostatic protection and PTC used in previous generations of USB are no longer sufficient to provide comprehensive and effective protection. Littelfuse's PTC product has been selected as the most suitable circuit protection product for USB3.0. It can protect USB3.0 ports with a maximum current of 900mA and will not trip even at a maximum operating temperature of 60℃.

In terms of LED lighting, Littelfuse provides a comprehensive solution. Using the triac components of the Q6008LH1LED and Q6012LH1LED series of Littelfuse, only a few devices are needed to realize a very efficient AC circuit for controlling LED light output. By using two reverse parallel sensitive gate thyristor rectifiers (SCR) S4X8ES1 as the trigger device control circuit for voltage conduction, various light level outputs can be generated. In addition, the high-voltage 477 series fuse provides overcurrent protection on the DC side. The small NANO fuse can meet the working conditions of 250VAC and provide safe overcurrent protection for the LED power adapter. Littelfuse's PLED products provide open circuit protectors and overvoltage protection. It can be connected in parallel with each LED in the light string to bypass the LED lamp beads with open circuit failure to keep the rest of the light string working. The protector will also work when an overvoltage occurs in the circuit and causes an overcurrent in the light string, or when the electrodes are reversed.

Du Zhide said that Littelfuse attaches great importance to the Chinese market. The company has two major laboratories, one in Chicago and the other in Wuxi, China. They can provide timely feedback on the needs of different customers and even provide customized circuit protection solutions and solution testing.

Based on the solid foundation of circuit protection, Littelfuse has set its sights on very promising markets such as power control and sensors. Du Zhide said that it is expected that in the next 4 to 5 years, Littelfuse will expand its product lines in these two fields, leading the power control and sensor markets while maintaining its market position in the circuit protection field.