TRANSFORMER FOR SIC/GAN DRIVE APPLICATIONS
LLC transformer specifically designed for SiC/GaN device switching
The launch of its first LLC transformer specifically designed for SiC/GaN device switching is announced by PULSE. The PMT6709NL delivers 2W of power which can be configured with LLC controllers such as the TI UCC25800-Q1 or the MPS MPQ18913 to provide positive and negative outputs for robust switch on/off. The extended creepage UI5 platform provides 3.75kVrms Hi-Pot isolation voltage in a compact (17.2x11x8.5mm max) SMD platform. This IATF design is compatible with full winding automation to fulfil the requirements of high reliability in automotive applications.
Designed for applications such as inverter motor drives that are driven by high voltage batteries, this platform satisfies the 9.1 mm min creepage requirement of IEC 61558-1 for basic insulation and a working voltage up to 850Vrms, or up to 450Vrms working voltage for applications that require reinforced insulation. A split bobbin is use to keep the interwinding capacitance to less the 2.5pF.
Flyback and Push-Pull topologies have traditionally been used for MOSFET drive circuits. Tight coupling is necessary to minimize transformer leakage inductance, which enhances the efficiency of the drive circuit. However a tightly coupled transformer design results in relatively high interwinding capacitance, limiting higher switching frequency and the full utilization of the benefits of using SiC/GaN Mosfets.
This is overcome with the two section PMT6907 winding construction and the LLC topology, where its higher leakage inductance does not impact on efficiency as it can be used as part of the resonant circuit.
It can even potentially eliminate the need for an external resonant inductor. The lower capacitance enables an order of magnitude reduction in the common-mode current injection through the bias transformer and the LLC soft-switching feature further reduces the EMI noise.
2W LLC/SiC & GaN drive Transformer
Reinforced insulation, 9.1mm creepage & 7mm clearance
3750Vrms Hi-Pot isolation voltage
Up to 900Vpk rated voltage
Footprint: 17.2 x 11x 8.5 mm max
Link to the Datasheet
Link to Rutronik 24