New-Tech Europe Magazine | Oct 2017 | Digital Edition

Back to Basics: Choosing the Perfect Regulator

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Buck, Boost or Buck-Boost Regulator? There are three basic categories: Buck - regulators with an output that is a lower voltage than the input Boost - regulators with an output that is a higher voltage than the input Buck-Boost - regulators that can supply output voltages that are higher, lower or the same as the input In most applications voltages are stepped down from the bus to the load and therefore buck regulators are commonly used. Other applications require the voltage to be increased with a boost regulator:

A voltage regulator provides two functions: changing the input voltage to a different level at the output and regulation (maintaining a constant output voltage despite changing load conditions). DC-DC Regulators are a key component in any power system, and so choosing the correct regulator is critical if an optimum solution is to be developed. Although engineers understand regulator functionality, less experienced engineers often find it difficult to identify the best regulator for their application. This blog post identifies criteria that anyone who is not an experienced power developer can use to ensure they choose the perfect regulator.

for example, if DC power must be transmitted using a long cable, the I2R losses can be reduced by boosting the voltage before transmission and then stepping it down again at the load. In battery applications buck-boost regulators are often used to provide a constant stable voltage, overcoming the change of output voltage that is seen as batteries charge and discharge. Nominal Inputs and Outputs Many systems have clear requirements for input and output voltage – for example you may need to step down a 12V rail to 3.3V. For many applications, there

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