At present, whether it is automobiles, industrial equipment, medical equipment, new energy equipment, or household appliances, the complexity of its internal components and the harshness of the use environment are increasing day by day. When the electrical supply is unstable, if there is no efficient and stable protection measures, the damage of a single component will cause the equipment to shut down. economic losses. Lightning is the representative of many harsh environments where electrical and electronic equipment is used. Statistics from a county in my country show that the equipment damage caused by overvoltage caused by lightning accounts for 70.11% of the whole, and the loss of a single work unit can reach hundreds of thousands of yuan. Coupled with the increasingly stringent and diverse functional requirements of consumers today, circuit protection components have developed from glass tube fuses to a huge branch of electronic components. In order to help equipment manufacturers cope with the increasingly complex and changeable market environment and improve product market competitiveness, Bourns, a world-renowned electronic component manufacturer and supplier, has launched GMOV 8482 ; series of overvoltage protection components (hereinafter referred to as GMOV) ™ series).

Figure: Composition of GMOV™ series products

Currently, many device manufacturers choose to use a discrete combination of metal oxide varistors (MOVs) and gas discharge tubes (GDTs) to provide a robust, low-leakage front-end protection scheme against voltage transients. "Bourns innovatively combines its patented and space-saving FLAT® Technology Flat Gas Discharge Tube (FLAT-GDT) with a metal oxide varistor ( MOV) to create a compact and enhanced overvoltage combined protector. The GMOV™ series is more compact and robust, meeting the stringent requirements for miniaturized devices, combined with the high-voltage freewheeling interrupting capability of MOVs, solving the The freewheeling problem of GDT alone is adopted. At the same time, GMOV™ effectively eliminates heat damage and most other damages caused by MOV leakage current or overcurrent, thereby forming a protection solution with zero standby energy consumption. Since the inter-electrode capacitance is less than 4pF, which can be used for power supply and some signal line protection scenarios at the same time; standard 14mm and 20mm packages are compatible with MOV product packages, and meet the safety requirements of UL1449 in application scenarios." Under low frequency conditions, the voltage limit of GMOV™ series is equal to a single The sum of the voltage limits of the MOV and GDT components. In practical applications, the actual withstand voltage requirement of the circuit can be improved. When there is a surge voltage in the device, the GDT in the GMOV™ family can quickly turn on and connect the MOV in less than a microsecond, controlling the surge voltage to an acceptable level. When the surge voltage passes, the line voltage drops and passes through the MOV, turning off the GDT. Once the GDT is turned off, the GMOV™ series disconnects the MOV from the line as before. The function of the GMOV™ series is a very special "symbiotic" relationship, in which GDT and MOV work together, which is the key to its long-term stability and effectiveness

Figure: GMOV™ series circuit diagram

Compared to MOV devices, the GMOV™ series of overvoltage protection components are capable of handling transients and transient overvoltage spikes, avoiding degradation and failure in harsh environments, significantly increasing the MTBF (mean time between failures) of MOVs, providing more High level of performance and safety. The GMOV™ series is available in standard 14 mm and 20 mm MOV packages and is a drop-in replacement for standard 14 and 20 mm MOVs. Figure: Product Dimensions (unit: mm) The following figure shows the performance of the MOV device and the GMOV™ family in practical applications: As can be seen from the diagram, in an assumed 120 Vrms application, the standard 130V MOV device is at the clamping voltage , leakage, aging characteristics and response to transient overvoltage (TOV) are the worst; 275V MOV devices can help mitigate leakage and aging problems, however a transient overvoltage condition can still cause excessive leakage and device damage; the third example shows that when the 130V TMOV/iMOV device integrates thermal protection, the basic performance is similar to the 130V MOV device, but there is still the possibility of failure when a transient overvoltage occurs; in comparison, the GMOV™ series of The clamping voltage is similar to the 130V MOV device, but better than the 275V MOV device, and the leakage, aging characteristics, and response to transient overvoltage (TOV) all show superior performance. The figure below also allows us to more intuitively see the superior performance of the GMOV™ series in protecting equipment. It can be seen from the diagram that the Clamp Transition Time to reach Vfp represents the time required for the GDT to start, and the clamp transition time of GMOV™ series products can last less than 0.3µs. In conclusion, the GMOV™ series is ideal for AC and DC power supply applications requiring high performance circuit protection. Therefore, the GMOV™ series can be used in all major markets and verticals such as industrial, consumer products, medical and communications. Application cases for the GMOV™ series include power and data port protection for surge protection devices (SPDs), white goods, chargers, solar (new energy storage), medical electronics (low/medium risk), and power protection applications for smart grids . We can even argue that almost many applications powered by AC or DC can use the GMOV™ series for overvoltage protection. Markets such as smart grid and energy storage are a good example, where the GMOV™ series can reduce leakage currents, a product feature that is extremely attractive in the energy market, especially in the presence of voltage stress and transient overvoltages , the need to prevent safety hazards such as fire caused by MOV burst. Additionally, the 4pF class capacitance advantage of the GMOV™ family allows for exceptionally high data rates for power data line communications. At present, the GMOV™ series products have been launched. As an agent of Bourns, Shijian will add the GMOV™ series to the product line catalog and solutions, so that the equipment of Shijian's customers can enjoy the advantages of the GMOV™ series. Comes with high-quality, long-lasting, all-round protection.

Figure: GMOV™-14D Series Product List (1)