ADP3198

Rev. 2 | Page 2 of 31 | www.onsemi.com

TABLE OF CONTENTS

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

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

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

Functional Block Diagram...............................................................1

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

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

Test Circuits .......................................................................................5

Absolute Maximum Ratings ............................................................6

ESD Caution ..................................................................................6

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

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

Theory of Operation.......................................................................10

Start-Up Sequence ......................................................................10

Phase Detection Sequence .........................................................10

Master Clock Frequency ............................................................11

Output Voltage Differential Sensing ........................................11

Output Current Sensing .............................................................11

Active Impedance Control Mode .............................................11

Current Control Mode and Thermal Balance.........................11

Voltage Control Mode ................................................................12

Current Reference .......................................................................12

Enhanced PWM Mode...............................................................12

Delay Timer .................................................................................12

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

Current-Limit, Short-Circuit, and Latch-Off Protection ......13

Dynamic VID ..............................................................................13

Power-Good Monitoring ...........................................................13

Output Crowbar..........................................................................14

Output Enable and UVLO.........................................................14

Thermal Monitoring...................................................................14

Application Information ................................................................19

Setting the Clock Frequency .....................................................19

Soft Start Delay Time .................................................................19

Current-Limit Latch-Off Delay Times.....................................19

Inductor Selection.......................................................................19

Current Sense Amplifier ............................................................20

Inductor DCR Temperature Correction..................................21

Output Offset...............................................................................22

Power MOSFETs .........................................................................24

Ramp Resistor Selection ............................................................25

COMP Pin Ramp ........................................................................25

Current-Limit Setpoint ..............................................................25

Feedback Loop Compensation Design ....................................25

Thermal Monitor Design...........................................................27

Shunt Resistor Design ................................................................28

Tuning the ADP3198..................................................................28

Layout and Component Placement..........................................29

Outline Dimensions........................................................................31

Ordering Guide ...........................................................................31

REVISION HISTORY

01/08 - Rev 2: Conversion to ON Semiconductor

8/06—Rev. 0 to Rev. A.

6/06—Revision 0: Initial Version