Introduction to Digital Power Conversion
XMC4000/1000 Family
Comparison of Power Conversion Methods
Application Guide
7
V1.0, 2015-01
2
Comparison of Power Conversion Methods
2.1
What is Power Conversion
Power conversion is the conversion of electric energy from one form to another. As long as it does not
concern electro-mechanic equivalent energy that consumes energy (e.g. motors) or produces energy
(e.g. generators), then it is about pure power transfer, in any form, from the following categories:
Table 1
Power conversion categories
Category
Type
General Purpose
DC / DC
DC-to-DC converter
Regulator / Stabilizer / Voltage Adapter
AC / DC
AC-to-DC converter
Rectifier / Mains Power Supply Unit (PSU)
DC / AC
AC-to-DC converter
Inverter
AC / AC
AC-to-AC converter
Transformer / Variable frequency Converter
2.2
Why Power Conversion
According to the global environmental context, each case of electric energy transfer between an
energy source and an energy consuming unit, should consume as little energy as possible to perform
the task by optimal adaption. This is generally unachievable without some form of power conversion.
2.3
Methods of Power Conversion
There are two significantly different ways to convert a DC supply voltage to another DC voltage:
Linear Power Conversion
Switch Mode Power Conversion
When Switch Mode is chosen (e.g. for High Power) the next choice is between:
Analog (discrete) control
Digital (ASIC/MCU/DSP) control
2.3.1
Linear Mode Power Conversion
A Linear DC/DC Converter output/input voltage ratio is < 1 and the output/input current ratio is < 1, so
there is always a significant power loss.
Linear voltage regulators meet such demands as
‘Easy-to-Use’, Accuracy, Low Cost and EMC. They
are therefore the
“best-choice” in low power / low current DC-converters.
