ADP1822

Rev. B | Page 2 of 24

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications....................................................................................... 1

General Description ......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

Absolute Maximum Ratings............................................................ 5

ESD Caution.................................................................................. 5

Simplified Block Diagram ............................................................... 6

Pin Configuration and Function Descriptions............................. 7

Typical Performance Characteristics ............................................. 9

Theory of Operation ...................................................................... 12

Current-Limit Scheme............................................................... 12

Output Voltage Margining ........................................................ 12

Output Voltage Tracking ........................................................... 12

Soft Start ...................................................................................... 12

High-Side Driver (BST and DH).............................................. 13

Low-Side Driver (DL) ................................................................ 13

Input Voltage Range ................................................................... 13

Setting the Output Voltage ........................................................ 13

Switching Frequency Control ................................................... 13

Compensation............................................................................. 13

Power-Good Indicator............................................................... 13

Shutdown Control...................................................................... 13

Application Information................................................................ 14

Selecting the Input Capacitor ................................................... 14

Output LC Filter ......................................................................... 14

Selecting the MOSFETS ............................................................ 15

Setting the Current Limit .......................................................... 15

Feedback Voltage Divider ......................................................... 16

Setting the Voltage Margin........................................................ 16

Compensating the Regulator .................................................... 16

Setting the Soft Start Period...................................................... 19

Synchronizing the Converter.................................................... 19

Setting the Output Voltage Tracking ....................................... 19

Application Circuits ....................................................................... 20

Outline Dimensions ....................................................................... 21

Ordering Guide .......................................................................... 21

REVISION HISTORY

8/06—Rev. A to Rev. B

Change to Title.................................................................................. 1

Change to General Description ...................................................... 1

Changes to Figure 6.......................................................................... 9

Changes to Output Voltage Margining Section.......................... 12

Changes to Table 4.......................................................................... 12

1/06—Rev. 0 to Rev. A

Changes to Figure 1.......................................................................... 1

Changes to Table 1............................................................................ 3

Changes to Input Voltage Range Section .................................... 13

Changes to Selecting the Input Capacitor Section ..................... 14

Added Equation 1; Renumbered Sequentially............................ 14

Changes to Equation 7 and Equation 8 ....................................... 15

Changes to Selecting the MOSFETS Section .............................. 15

Added Equation 9; Renumbered Sequentially ........................... 15

Changes to Equation 10................................................................. 15

Changes to Equation 22................................................................. 17

Changes to Compensating the Regulator Section...................... 17

Changes to Figure 19 and Figure 20............................................. 17

Changes to Equation 27................................................................. 17

Changes to Equation 34................................................................. 18

7/05—Revision 0: Initial Version