Discrete UMTS Onboard DC/DC Converter

On board power supplies for UMTS base station applications are challenging and require special design considerations particularly for low noise output voltages and low EMI interference. This paper gives an insight to the concept called "3^rd generation power management". Every base station module has its own galvanic insulated power supply and distribution depending on the type of board. Additional DC/DC step down converters with multiple output voltages may be needed. With this power distribution, every board is dependent only on the 48 V backplane voltage instead of on different low voltages. For this application an 80 W DC/DC converter is presented together with additional functions and protection features. The selection of the most appropriate from the variety of possible converter topologies is explained on the basis of the core controller stage