Integrated resonant transformer saves PCB space
A resonant transformer integrates an inductor in a single package for inductor-inductor-capacitor (LLC) applications. Vishay Intertechnology said the MRTI5R5EZ saves space and simplifies PCB layout in LLC (inductor-inductor-capacitor) applications.
It features tuneable magnetising and leakage inductance, minimal parasitic variation and “excellent” heat dissipation performance, Vishay added.
The 5.5kW Vishay Custom Magnetics MRTI5R5EZ is believed to be the first of its kind to use a second middle transformer leg to complete the resonant inductor portion of the circuit. Vishay pointed out that other implementations require an additional magnetic core to deliver the same performance. The MRTI5R5EZ’s construction saves space and simplifies designs by eliminating the need for interconnects or jumpers from the resonant inductor to the transformer’s winding.
The MRTI5R5EZ will be used in on-board chargers and half- or full-bridge resonant power supply transformers in industrial controls, solar inverters, military, avionics and construction equipment. In addition to providing a customisable turns ratio, the transformer’s losses can be moved from the core to the coil as required to optimise performance and heat dissipation-. The transformer’s minimal parasitic variation is claimed to optimise capacitor selection.
Operating frequencies range from 100 to 350kHz and rated power is from 4.0 to 6.0kW with an input range of 400 to 800V. Rated current is up to 28A. Isolation voltage is 2,500V.
The transformer includes a bracket for cold plate mounting with raised bosses and there are flush mount options available. The transformer design has M4 ring terminals as standard and there is a choice of customisable lead lengths and terminal types available. The MRTI5R5EZ can be provided with a thermal gap pad on the mounting surface.
Samples and production quantities are available now, with lead times of four weeks for samples and 16 to 20 weeks for production quantities.
Vishay manufactures a wide portfolio of discrete semiconductors and passive electronic components for designs in the automotive, industrial, computing, consumer, telecommunications, military, aerospace and medical markets.