l6599atn STMicroelectronics, l6599atn Datasheet - Page 17

• Manufacturer Part Number: l6599atn
• Description: Improved High-voltage Resonant Controller
• Manufacturer: STMicroelectronics

L6599AT
no-load consumption of this stage (0.5 1 W). There is no compliance issue because EMC
regulations on low-frequency harmonic emissions refer to nominal load, so no limit is
imposed when the converter operates with light or no load.
To do so, the L6599AT provides pin 9 (PFC_STOP): it is an open collector output, normally
open, that is asserted low when the IC is idle during burst-mode operation. This signal is
externally used for switching off the PFC controller and the pre-regulator as shown in
Figure 9
first
Figure 8.
Figure 9.
. When the L6599AT is in UVLO the pin is kept open, to let the PFC controller start
Load-dependent operating modes: timing diagram
How the L6599AT can switch off a PFC controller at light load
Doc ID 15534 Rev 1
Application information
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