STMicroelectronics 19 V - 75 W SMPS using the L6563 and the L6566A EVL6566A-75WES4 EVL6566A-75WES4 Ficha De Dados
Códigos do produto
EVL6566A-75WES4
Application information
L6563S
30/43
Doc ID 16116 Rev 4
Figure 40.
Tracking boost block
Figure 41.
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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