POWER & ENERGY EFFICIENCY HANDBOOK
Evaluating isolation techniques in dc/dc converters
Steve Roberts | Recom Power
Different isolation methods give different results. It’s important to know what to expect from converters that separate their input and output in a specific way.
Isolation in dc/dc converters has numerous uses besides just protection against electric shock. There are various grades of isolation that low-power dc/dc converters implement in different ways. Many dc/dc converters use an internal transformer to electrically (galvanically) separate the output from the input. This separation makes dc/dc converters versatile. Outputs that float with respect to the input prevent ground loops and reduce the potential for noise in electrical systems. Moreover, the output polarity
The RECOM RP-xxxx series uses potted-core transformer construction to offer 5.2 kVdc isolation test voltage rating in a compact SIP7 package (19.6 x 10.2 x 7 mm). This makes the RP series one of the most reliable high-isolation dc/ dc converters in the RECOM portfolio, used in demanding applications ranging from military aircraft to high-voltage test equipment.
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can be freely chosen. And, of course, the isolation barrier can prevent electric shock and reduce other hazards caused by faults. Because the output is isolated from the input, the choice of the ‘zero’ reference voltage for the input or output side is also arbitrary. For example, an isolated dc/dc converter with a 5-V output can be used to change voltage level and polarity (e.g. +5-V out from -48-V in), add to an existing voltage (e.g. generate +20 V from a +15-V supply) or create a dual output from a single supply (e.g. ±5 V from +5 V).
An example of a ring core transformer with functional isolation.
Potted - core transformer construction Step 1: Primary winding
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Step 2: Potting
Step 3: Lid fitted and secondary wound around case
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10/10/19 9:08 AM
