STEVAL-ISA011V1 STMicroelectronics, STEVAL-ISA011V1 Datasheet - Page 13

• Manufacturer Part Number: STEVAL-ISA011V1
• Description: BOARD EVAL VIPER12A LP AC/DC
• Manufacturer: STMicroelectronics
• Series: VIPER™r
• Type: AC/DC Switching Convertersr

Specifications of STEVAL-ISA011V1

• Design Resources: STEVAL-ISA011V1 Gerber Files STEVAL-ISA011V1 Schematic STEVAL-ISA011V1 Bill of Materials
• Main Purpose: AC/DC, Primary Side
• Outputs And Type: 1, Isolated
• Power - Output: 4.1W
• Voltage - Output: 4.5V
• Current - Output: 900mA
• Voltage - Input: 88 ~ 265VAC
• Regulator Topology: Flyback
• Frequency - Switching: 60kHz
• Board Type: Fully Populated
• Utilized Ic / Part: VIPer12A
• Input Voltage: 88 V to 265 V
• Output Voltage: 4.5 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: VIPER12ADIP-E
• Kit Application Type: Power Management - Voltage Regulator
• Application Sub Type: AC / DC Adapter
• Kit Contents: Board
• Rohs Compliant: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: VIPer12A
• Other names: 497-6413; STEVAL-ISA011V1

AN2272 - Application Note
Using the VIPer12A input current (I
Equation 20
Where,
G
V
I
G
Equation 21
Equation 22
PK
O
fly
ID
= voltage output,
= primary peak current, and
= flyback gain,
= feedback current-to-drain current gain (see VIPer12A datasheet for details).
The flyback pole value is expressed as:
Where,
p
C
R
ESR
The flyback zero value (for two poles, one zero compensation network) is expressed
as:
Where,
z
One pole is located at zero frequency in order to maximize the precision of the
regulation. Compensation zero was used in order to compensate the p
it has to be located between one-half and double the p
compensation network is used to compensate flyback zero due to the ESR.
fly
fly
OUT
L
= inductor resistance, and
= flyback zero.
= flyback pole reference,
OUT
= output capacitor (see C
= equivalent series resistor output.
p
fly
z
=
FB
fly
11
----------------------------------------------------------------------------------
C
Rev. 1
) to the feedback pin and G
OUT
,
=
G
STEVAL-ISA011V1 Schematic on page 30
fly
------------------------------------------- -
C
OUT
=
R
----------
I
V
PK
L
O
+
2
ESR
1
2 ESR
G
ID
OUT
STEVAL-ISA011V1 Board Design
O UT
fly
frequency. The last pole of the
fly
values,
fly
and, typically,
),
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