STMicroelectronics EVAL BOARD FOR L6563 EVL6563H-250W EVL6563H-250W Fiche De Données
Codes de produits
EVL6563H-250W
L6563H
Application information
Doc ID 16047 Rev 3
31/49
Figure 43.
Tracking boost block
Figure 44.
Tracking output voltage vs Input voltage characteristic with TBO
6.6 Inductor
saturation detection
Boost inductor's hard saturation may be a fatal event for a PFC pre-regulator: the current up-
slope becomes so large (50-100 times steeper, see
slope becomes so large (50-100 times steeper, see
) that during the current sense
propagation delay the current may reach abnormally high values. The voltage drop caused
by this abnormal current on the sense resistor reduces the gate-to-source voltage, so that
the MOSFET may work in the active region and dissipate a huge amount of power, which
leads to a catastrophic failure after few switching cycles.
by this abnormal current on the sense resistor reduces the gate-to-source voltage, so that
the MOSFET may work in the active region and dissipate a huge amount of power, which
leads to a catastrophic failure after few switching cycles.
However, in some applications such as ac-dc adapters, where the PFC pre-regulator is
turned off at light load for energy saving reasons, even a well-designed boost inductor may
turned off at light load for energy saving reasons, even a well-designed boost inductor may
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