STEVAL-ISA011V1 STMicroelectronics, STEVAL-ISA011V1 Datasheet - Page 14

• 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

STEVAL-ISA011V1 Board Design
14/33
Equation 23
Loop Gain crossover frequency is the last calculation required to define the
compensation network. In this design, the crossover frequency selected is as high as
2.5kHz to provide the converter with good bandwidth.
The Transfer Function output control is expressed as:
Where,
CTR = optocoupler Current Transfer Ratio
R
Note: Using these resistance and capacitance values as guidelines will provide the
user with a stable loop as well as the required converter bandwidth.
V
I
FB
FB
O
= VIPer12A feedback pin input impedance.
= output voltage ripple,
= VIPer12A feedback pin current,
------------------------
I
V
FB
O
s
s
=
-----------------------------------
R
6
Rev. 1
CTR
R
8
C
8
---------------------------------------------------------- -
s 1 s R
1 s R
+
+
9
FB
C
8
C
AN2272 - Application Note
5