Datasheet

ADP1621 Data Sheet
Rev. B | Page 2 of 32
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Typical Application Circuit ............................................................. 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution .................................................................................. 5
Simplified Block Diagram ............................................................... 6
Pin Configuration and Function Descriptions ............................. 7
Typical Performance Characteristics ............................................. 8
Theory of Operation ...................................................................... 12
Control Loop ............................................................................... 12
Current-Sense Configurations .................................................. 12
Current Limit .............................................................................. 13
Undervoltage Lockout ............................................................... 13
Shutdown ..................................................................................... 13
Soft Start ...................................................................................... 13
Internal Shunt Regulators .......................................................... 13
Setting the Oscillator Frequency and Synchronization
Frequency .................................................................................... 13
Application Information: Boost Converter ................................. 14
ADIsimPower Design Tool ....................................................... 14
Duty Cycle ................................................................................... 14
Setting the Output Voltage ........................................................ 14
Inductor Current Ripple ............................................................ 14
Inductor Selection ...................................................................... 14
Input Capacitor Selection .......................................................... 15
Output Capacitor Selection ....................................................... 15
Diode Selection ........................................................................... 15
MOSFET Selection ..................................................................... 16
Loop Compensation .................................................................. 16
Slope Compensation .................................................................. 17
Current Limit .............................................................................. 18
Light Load Operation ................................................................ 18
Recommended Component Manufacturers ........................... 19
Layout Considerations ................................................................... 20
Efficiency Considerations ............................................................. 21
Examples of Application Circuits ................................................. 22
Standard Boost Converter—Design Example ........................ 22
Bootstrapped Boost Converter ................................................. 23
SEPIC Converter Circuit ........................................................... 27
Low Voltage Power-Input Circuit ............................................ 27
LED Driver Application Circuits ............................................. 28
Related Parts .................................................................................... 30
Outline Dimensions ....................................................................... 31
Ordering Guide .......................................................................... 31
REVISION HISTORY
6/12—Rev. A to Rev. B
Change to Features Section ............................................................. 1
Added ADIsimPower Design Tool Section ................................. 14
Change to Table 6 ........................................................................... 30
Updated Outline Dimensions ....................................................... 31
Changes to Ordering Guide .......................................................... 31
12/06—Rev. 0 to Rev. A
Changes to Table 1 ............................................................................ 3
Changes to Table 2 ............................................................................ 5
Added Table 3 .................................................................................... 5
Changes to Table 5 .......................................................................... 19
Changes to Ordering Guide .......................................................... 31
7/06—Revision 0: Initial Version