AN833 Datasheet, PDF (3/3 Pages) STMicroelectronics – FREQUENCY MODULATION ON L4981B

AN833 APPLICATION NOTE
eg. designing a 100kHz minimum fsw with a modulation depth » 20%:
f_SW = 124KHz = -₂---₄----_â‹----₁---₀----_–--₃-²---_â‹-^.-⁴-₀---⁴-_.-₈----₂----_â‹---₁----₀---_–---₉-
fIn this way the advantage, in terms of reduction of the peak of energy in the noise spectrum, is remarkable. On
the other hand the increase of switching losses can be neglected because the maximum frequency occurs at
the minimum line current.
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