Table of Contents
Table of Contents
Table of Contents .......................................................................................................................................5
List of Figures.............................................................................................................................................7
List of Tables ..............................................................................................................................................9
1
Signal Description.......................................................................................................................11
Pin Configurations...........................................................................................................................................11
Pin Descriptions ..............................................................................................................................................11
1.1
1.2
2
Electrical Specifications .............................................................................................................13
Absolute Maximum Ratings ...........................................................................................................................13
Recommended Operating Conditions .............................................................................................................14
Electrical Characteristics ................................................................................................................................15
2.1
2.2
2.3
3
Functional Description................................................................................................................19
Overview .........................................................................................................................................................19
Signal Process and Functions.........................................................................................................................20
3.1
3.2
4
Functional Characteristics .........................................................................................................21
VDD Characteristics ........................................................................................................................................21
VFB Characteristics for Over Voltage Protection.............................................................................................23
Switching Frequency Characteristics..............................................................................................................24
Over Current Threshold Characteristics..........................................................................................................25
4.1
4.2
4.3
4.4
5
Design and Applications Information........................................................................................27
Input Voltage Resistor Divider on VIN Pin.......................................................................................................28
Isolated Voltage Loop and Output Voltage Feedback on FB Pin....................................................................30
5.1
5.2
5.2.1
5.2.2
5.2.3
Resistor Divider Design for Output Voltage......................................................................................31
Compensation Network Design ........................................................................................................31
RS2 and Rf1 Design.........................................................................................................................33
5.3
Current Sensing and Over Current Protection ................................................................................................34
5.3.1
5.3.2
5.3.3
5.3.4
Current Sensing Through ISNS Pin..................................................................................................34
Average Current Signal and Over Power Limitation .........................................................................35
Cycle by Cycle Current Protection through OCP Pin........................................................................36
Peak Current and Average Current Relationship .............................................................................38
5.4
5.5
5.6
SW Pin to MOSFET Gate ...............................................................................................................................39
VDD, Signal Ground (SGND) and Power Ground (PGND).............................................................................39
90W/20V Signal Stage PFC Adaptor Schematic and Bill of Materials (BOM).................................................41
Copyright © 2009 Marvell
Doc. No. MV-S104983-01 Rev. A
Page 5
October 5, 2009, Preliminary
Document Classification: Proprietary
MARVELL [ MARVELL TECHNOLOGY GROUP LTD. ]
