MTM power has released a set of primary switched DC/DC converters, PCMDS80, designed specifically for applications in rail and automotive, but also suitable for use in industrial and telecomms applications. They are available with 80W output power and operate according to the single transistor forward converter topology with a frequency of 50kHz.
With the help of a transformer and a secondary linear choke, a galvanically isolated output voltage (12, 13.8, 24, 27.6 or 48V) is produced which is adjusted by PWM according to the current mode principle. The converters are available with three wide input ranges thus covering the battery voltages of 24, 36, 48, 60, 72, 80, 96 and 110V acc. EN 50 155. The base plate version features dimensions of 119x100x40mm, and the heat sink version 119x115x65mm.
Thermoselective vacuum encapsulation (EP 1 987 708, U.S. Patent No. 8,821,778 B2) guarantees homogeneous heat dissipation within the modules as well as an excellent resistance against environmental influences such as shock, vibration and humidity. The converters need no ground load and are short-circuit protected by primary and secondary power limiting.
The PCMDS80 converters are maintenance-free, prepared for use in devices with Protection Class II, and require no external components besides protection fuses. They fulfil the low voltage directive as well as the EN 50 155 standard for electronic equipment in railway applications. The converters feature a mechanically and electrically rugged design using SMD technology and undergo an automatic piece-by-piece test. Cooling is achieved by free convection. The converters without heat sink must be mounted on a heat-dissipating surface.