A range of primary switched DC/DC converters with 400W output power has been released by MTM Power, especially designed for automotive applications. They operate according to the push-pull principle; i. e. the input DC voltage is chopped by two push-pull working transistors with a frequency of approximately 60kHz.
With the help of a transformer and a secondary linear choke, a galvanically isolated output voltage (12 or 24V) is produced which is adjusted by pulse-width modulation according to the current mode principle. The PCMD400W series is available with input voltages of with 36, 72, 80 and 110VDC and can be connected via screw connectors.
The devices are available in an aluminium case and measure 150x86x55mm. Due to this compact design, they are also suitable for applications where only little space is available. The converters need no ground load, are maintenance free and short-circuit protected by primary and secondary power limitation. They are vacuum potted, prepared for use in devices with Protection Class II and fulfil the low voltage directive.
As an option, they can be available for use in railway applications. Further features are a mechanically and electrically rugged design using SMD-technology and an automatic piece-by-piece test. To ensure a smooth operation, it is necessary to mount the converters on a heat-dissipating surface.