Vishay Intertechnology, Inc has introduced a new resonant transformer, the MRTI5R5EZ, for Inductor-Inductor-Capacitor (LLC) applications, where the transformer and integrated inductor are packaged in a single package. The 5.5 kW Vishay Custom Magnetics MRTI5R5EZ saves PCB space while simplifying layout, reducing the number of components required to mount, fully adjustable magnetization and leakage inductance, and low parasitics.
The recently released device is the first transformer to utilize an auxiliary intermediate transformer branch to form the resonant inductive portion of the circuit. Additional magnetic cores are required for other devices to achieve the same function. This unique construction not only saves space, but also simplifies the design by eliminating the need for interconnects or jumpers between the resonant inductor and transformer windings.
The MRTI5R5EZ is suitable for on-board chargers as well as industrial control, solar inverter, defense, avionics and construction equipment half-bridge/full-bridge resonant power transformers. In addition to customizing turns ratios for these applications, transformer losses can be transferred from the core to the coil as needed, enabling superior performance and heat dissipation, while excellent parasitic parameters optimize capacitor selection.
The devices operate at frequencies from 100 kHz to 350 kHz and are rated at 4 kW to 6 kW, with input voltages of 400 V to 800 V and current ratings of 28 A. The MRTI5R5EZ has a rated insulation voltage of 2500 V. The transformer includes a bracket for cold plate mounting, optionally raised or flush. The standard connector of the transformer is an M4 ring connector, the lead length and connector type can be customized, and the device is provided with thermal pads for fixing the surface.
