The differences between non-isolated buck,boost and buck-boost converters

摘要

Non-isolated buck,boost and buck-boost topologies are found in many AC-DC power supplies and non-isolated DC-DC converters. Although many of the patents of DC-DC converters were filed in the 1970s,their simplicity, low cost and very high efficiencies make these devices widely used even now. Standard, off-the-shelf products are still being introduced, taking advantage of new techniques like digital control, improved components and more efficient magnetic materials. The main difference between an isolated and a non-isolated DC-DC converter is the transformer, or lack of it. In an isolated converter, the transformer provides a safety barrier between the DC input (primary) and the DC output (secondary). Non-isolated converters are powered by low-voltage batteries or by an AC-DC power supply which already contains the safety barrier.