ADP3191

Rev. 0 | Page 2 of 28

TABLE OF CONTENTS

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

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

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

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

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

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

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

Pin Configuration and Function Descriptions............................. 6

Typical Performance Characteristics and Test Circuits............... 7

Theory of Operation ........................................................................ 8

Startup Sequence .......................................................................... 8

Master Clock Frequency.............................................................. 8

Output Voltage Differential Sensing .......................................... 8

Output Current Sensing .............................................................. 8

Active Impedance Control Mode............................................... 9

Current-Control Mode and Thermal Balance.......................... 9

Voltage Control Mode.................................................................. 9

Soft Start ........................................................................................ 9

Current-Limit, Short-Circuit, and Latch-Off Protection...... 10

Dynamic VID.............................................................................. 10

Power Good Monitoring ........................................................... 12

Output Crowbar ......................................................................... 12

Output Enable and UVLO ........................................................ 12

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

Setting the Clock Frequency ..................................................... 14

Soft Start and Current-Limit Latch-Off Delay Times ........... 14

Inductor Selection ...................................................................... 14

Designing an Inductor............................................................... 15

Output Droop Resistance.......................................................... 15

Inductor DCR Temperature Correction ................................. 16

Output Offset .............................................................................. 16

COUT Selection ............................................................................. 17

Power MOSFETs......................................................................... 18

Ramp Resistor Selection............................................................ 19

COMP Pin Ramp ....................................................................... 19

Current-Limit Setpoint.............................................................. 19

Feedback Loop Compensation Design.................................... 19

CIN Selection and Input Current di/dt Reduction.................. 21

Tuning the ADP3191/ADP3191A............................................ 22

Replacing the ADP3181 with the ADP3191........................... 24

Choosing Between the ADP3191 and the ADP3191A ........ 24

RAMPADJ Filter......................................................................... 24

Shunt Resistor Design................................................................ 25

Layout and Component Placement.............................................. 26

General Recommendations....................................................... 26

Power Circuitry Recommendations ........................................ 26

Signal Circuitry Recommendations......................................... 26

Outline Dimensions ....................................................................... 27

Ordering Guide .......................................................................... 27

REVISION HISTORY

3/06—Revision 0: Initial Version