Gate Drive Transformers Information
Gate drive transformers are used to modify the voltage level to a gate. They also provide impedance matching and voltage isolation. Most gate drive transformers are used with high-speed switching devices such as field effect transistor (FET) and insulated gate bipolar transistor (IGBT) electronics. Pulse transformers are gate drive transformers that deliver a pulse or series of pulses to a semiconductor gate. Trigger transformers use a voltage pulse to initiate an action or event. Like other gate drive transformers, they are designed to minimize winding capacitance and leakage inductance. Performance specifications for gate drive transformers include operating frequency range, direct current resistance (DCR), output voltage, power rating, isolation or high potential (hipot) level, operating temperature and maximum dimension. Direct current resistance (DCR is the resistance of the transformer’s winding as measured with DC current. It is usually specified as a maximum rating. Isolation or hipot level is the maximum voltage that can be applied to a gate drive transformer without breaking the winding or dielectric.
Gate drive transformers differ in terms of core type, package type, and packing method. Core types EE, EER, EFD, ET, EP, EPS, and ETD have an E-shaped core with a bobbin structure. The PQ core has a larger surface area to dissipate greater amounts of heat. The RM core is used by both transformers and inductors. Integrated circuit (IC) package types for gate drive transformers include flat pack (FPAK), single in-line package (SIP), dual in-line package, and small outline integrated circuit (SOIC). Board-level components can use either surface mounted technology (SMT) or through hole technology (THT). SMT adds components to a printed circuit board (PCB) by soldering component leads to the top surface of the board. Through hole technology (THT) mounts components by inserting leads through holes and then soldering the leads in place on the opposite side of the board. Waveguide assemblies and connectorized gate drive transformers are also available. In terms of packing methods, gate drive transformers can be packed in trays, tubes, or tape reel assemblies. Bulk-pack products are distributed as individual parts.
Gate drive transformers are certified and approved by organizations such as the American National Standards Institute (ANSI), the Canadian Standards Association (CSA), the International Electrotechnical Commission (IEC), Underwriters Laboratories (UL), TÜV Rheinland/Berlin-Brandenberg (TUV), and Verband Deutscher Elektrotechniker (VDE). Gate drive transformers that are sold in European Union (EU) nations must comply with the Restriction of Hazardous Substances (RoHS) and Waste Electrical and Electronics Equipment (WEEE) directives.