EVL6563S-100W STMicroelectronics, EVL6563S-100W Datasheet - Page 27
![EVAL BOARD FOR L6563(100W)](/photos/37/57/375793/evl6563s-100_sml.jpg)
EVL6563S-100W
Manufacturer Part Number
EVL6563S-100W
Description
EVAL BOARD FOR L6563(100W)
Manufacturer
STMicroelectronics
Type
Power Factor Correctionr
Specifications of EVL6563S-100W
Main Purpose
Power Management, Power Factor Correction
Embedded
No
Utilized Ic / Part
L6563
Primary Attributes
100W Power Factor Correction and Preregulator Combination
Secondary Attributes
Transition Mode & Active Tracking Boost Function.
Board Size
90 mm x 83 mm
Maximum Operating Temperature
+ 60 C
Operating Supply Voltage
90 V to 265 V
Product
Power Management Modules
Dimensions
90 mm x 83 mm
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
L6563S
Other names
497-10490
L6563S
6.4
Figure 38. THD optimizer circuit
THD optimizer circuit
The L6563S is provided with a special circuit that reduces the conduction dead-angle
occurring to the AC input current near the zero-crossings of the line voltage (crossover
distortion). In this way the THD (total harmonic distortion) of the current is considerably
reduced.
A major cause of this distortion is the inability of the system to transfer energy effectively
when the instantaneous line voltage is very low. This effect is magnified by the high-
frequency filter capacitor placed after the bridge rectifier, which retains some residual
voltage that causes the diodes of the bridge rectifier to be reverse-biased and the input
current flow to temporarily stop.
To overcome this issue the device forces the PFC pre-regulator to process more energy
near the line voltage zero-crossings as compared to that commanded by the control loop.
This will result in both minimizing the time interval where energy transfer is lacking and fully
discharging the high-frequency filter capacitor after the bridge.
Figure 38
shows the internal block diagram of the THD optimizer circuit.
Doc ID 16116 Rev 4
Application information
27/43