Custom specific design versus application of standardised power modules

One of the most significant decisions during the development of a DC/DC power supply is to find out the best alternative for the specified requirements: using standard power modules or developing a custom specific design. This paper reflects the advantages and disadvantages of both, discussing important items that the designer has to consider on this point. It is focused on decentralised DC/DC power supply architecture for telecommunication applications. Most items discussed are also valid for other power supply solutions. The paper ends with the presentation of a power supply unit of the Siemens Base Station System, which led finally to a custom specific design.