Designers and engineers all have their specialty, but not everyone knows how to design a stable isolated DC/DC power supply. There are many topologies for different requirements and many decisions to make that affect the size and performance of the power supply. One needs to consider the topology, switching frequency, ripple performance, and other design considerations. Designing a power supply will take time. Once a topology is chosen, the repeated process of simulating, prototyping, testing, and debugging can take months of development time. There are standard isolated DC/DC converters in the market, but not all may meet a users requirements. There could be issues of size, cost, isolation level, power, and number of outputs.