Half Bridge Converter: A power supply topology
that uses a bridge circuit, consisting of two switching
transistors, to drive the transformer primary.
Half bridge converters are typically confi gured as
a forward converter. See Bridge Converter.
Half Wave Rectifi er: A single diode circuit that
rectifi es 2 of an AC waveform.
Harmonic Distortion: For sinusoidal AC current
waveforms, the load current distortion caused by
the presence of multiple harmonics of the fundamental
frequency (the frequency of the AC mains
voltage). This decomposition is calculated through
Fourier analysis:
I(t)=I0 x sin(w0t+j0)+I1 x sin(w1t+j1)+ ...In x sin(wnt+jn)
Where: IO = Amplitude of the fundamental
In = Amplitude of the nth harmonic
wO = 2p x fO
fO = Frequency of the fundamental (50/60 Hz)
wn = Frequency of the nth harmonic
jO = Phase shift of the fundamental
jn = Phase shift of the nth harmonic
Based on this, the distortion factor is calculated as:
K =
Contents of Harmonics
rms Value
Head Room: For a series pass regulator, refers
to the difference between the input and output
voltages.
Heat Flux: The fl ow rate of heat across or through
a material. Given in units of W/cm2.
Heat Rise: The increase in component/subassembly
temperature caused by self-heating or
heat absorption.