EVL6566A-75WADP STMicroelectronics, EVL6566A-75WADP Datasheet - Page 5

• Manufacturer Part Number: EVL6566A-75WADP
• Description: BOARD EVAL FOR L6566A
• Manufacturer: STMicroelectronics
• Type: Power Factor Correctionr

Specifications of EVL6566A-75WADP

• 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
• Frequency - Switching: 65kHz
• 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 174 mm
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Regulator Topology: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: L6563, L6566A
• Other names: 497-6449

Principles of Operation and Application Tips
5
5.1 Voltage control
The voltage loop is controlled via a first trans-conductance operational amplifier, the resistor bridge R1,
R2, and the optocoupler which is directly connected to the output.
The relation between the values of R1 and R2 should be chosen as written in
where V
To avoid the discharge of the load, the resistor bridge R1, R2 should be highly resistive. For this type of
application, a total value of 100K
As an example, with R2 = 100K , V
Note that if the low drop diode is inserted between the load and the voltage regulation resistor bridge to
avoid current flowing from the load through the resistor bridge, this drop should be taken into account in
the above calculations by replacing V
5.2 Current control
The current loop is controlled via the second trans-conductance operational amplifier, the sense resistor
R
V
point is tied to the positive input of the current control operational amplifier, and its foot is to be connected
to lower potential point of the sense resistor as shown on the following figure. The resistors of this bridge
are matched to provide the best precision possible.
The control equation verifies:
where I
Note that the R
through it during full load operation.
sense
sense
Principles of Operation and Application Tips
, and the optocoupler.
threshold is achieved externally by a resistor bridge tied to the V
lim
out
is the desired limited current, and V
is the desired output voltage.
sense
resistor should be chosen taking into account the maximum dissipation (P
R1 = R2 x V
(or more) would be appropriate for the resistors R1 and R2.
out
out
V
I
R
lim
sense
= 4.10V, V
P
sense
by (V
lim
=
Ref
=
=
R
--------------------------------------- -
out
sense
5
/ (V
I
---------------------- -
I
+ V
lim
R
R
lim
Ref
V
R
5
4
out
is the threshold voltage for the current control loop.
ref
4
drop
+
) = 1.210V, then R1 = 41.9K .
=
V
+
- V
R
V
ref
V
R
).
5
sense
R
Ref
sense
5
sense
)
Ref
voltage reference. Its middle
Equation
1.
Equation 1
Equation 2
Equation 3
Equation 4
TSM1014
5/10
lim
)