EVL6566A-75WES4 STMicroelectronics, EVL6566A-75WES4 Datasheet - Page 7

• Manufacturer Part Number: EVL6566A-75WES4
• Description: BOARD DEMO FOR L6563/LL6566A
• Manufacturer: STMicroelectronics
• Type: Power Factor Correctionr

Specifications of EVL6566A-75WES4

• Main Purpose: AC/DC, Primary and Secondary Side with PFC
• Outputs And Type: 1, Isolated
• Power - Output: 75W
• Voltage - Output: 19V
• Current - Output: 4A
• Voltage - Input: 90 ~ 264VAC
• Regulator Topology: Flyback
• Board Type: Fully Populated
• Utilized Ic / Part: L6563, L6566A, TSM1014
• Input Voltage: 90 V to 264 V
• Output Voltage: 19 V
• Dimensions: 78 mm x 170 mm
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: L6563S, L6566A
• Other names: 497-8834

AN2941
Operation of the “sensorless PFC” is explained as follows, referring to
Hence, properly selecting the time constant of the circuit, we can use the voltage across C
to feed the multiplier input of the L6563S because it is information about the instantaneous
value of the input voltage which is needed by the control part to shape the input current.
Figure 4.
Of course the C
to feed a stable feedback signal into the PFC controller error amplifier.
a)
where n is the winding turns ratio.
b)
c)
During the MOSFET OFF-time the voltage applied across the boost inductance is
the difference between the output and the input voltage. So D
and C
During the MOSFET ON-time the voltage applied across the boost inductor is V
(with reversed polarity) so D
D
Because C
charged is proportional to the PFC output voltage and can be used to get the
output voltage feedback signal:
2
to a voltage equal to:
Sensorless PFC operation theory
2
3
is charged via D
time constant has to be significantly longer than that of C
3
is in parallel to the series of C
Doc ID 15447 Rev 3
V
1
3
to:
=
1
V
V
is reverse biased and the capacitor C
out
2
n
=
V
−
1
V
V
=
Main characteristics and circuit description
in
out
V
+
n
n
in
−
V
V
n
in
in
1
=
and C
V
out
n
2
, the voltage at which it is
Figure 4
2
is reverse biased
1
1
and C
is charged via
:
2
in order
7/37
in
1