REV. 0

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a

ADP3422

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2001

IMVP-II-Compliant

Core Power Controller for Mobile CPUs

FUNCTIONAL BLOCK DIAGRAM

HYSTERESIS

AND

SHIFT-SETTING

VID4

VID3

VID2

VID1

VID0

CS+

CS–

ADP3422

VR

CLIM

CORE

PROGRAMMED

DAC

AND

FIXED

REFERENCE

VCC

VCC

VR

GND

COREFB

SS

DRVLSD

CLAMP

RAMP

REG

OUT

DACOUT

SWFB

EN

UVLO AND MAIN BIAS

SR CONTROL

PWRGD MONITOR

PWRGD BLANKER

SS-HICCUP TIMER AND OCP

OVP AND RVP

OP MODE

SELECTOR

POWER MANAGEMENT

SD

PWRGD

DPRSLP

DSLP

BOM

CPUSET

HYSSET

FSHIFT

DSHIFT

BSHIFT

FEATURES

Certified IMVP-II Controller

Excellent Transient Containment

Minimum Number of Output Capacitors

Fast, Smooth, Output Transition During VID Code Change

Current Limit with Hiccup Protection

Transient-Glitch-Free Power Good

Low Shutdown Current

Soft Start Eliminates In-Rush Current Surge

Adaptive Noise-Blanking Enhancement for Speed and

Stability

Highly Redundant Over-Voltage and Reverse-Voltage

Protection

Controls Synchronous Rectifier for Improved Battery Life

APPLICATIONS

IMVP-II Enabled Core DC/DC Converters

Fixed-Voltage Mobile CPU Core DC/DC Converters

Notebook/Laptop Power Supplies

Programmable Output Power Supplies

GENERAL DESCRIPTION

The ADP3422 is a hysteretic dc-dc buck converter controller to

power a mobile processor’s core. The optimized low voltage

design is powered from the 3.3 V system supply. The output

voltage is set by a 5-bit VID code. To accommodate the transition

time required by the newest processors for on-the-fly VID

changes, the ADP3422 features high-speed operation to allow a

minimized inductor size that results in the fastest change of

current to the output. To further allow for the minimum number

of output capacitors to be used, the ADP3422 features active

voltage positioning that can be optimally compensated to ensure a

superior load transient response. The output signal interfaces

with the ADP3415 MOSFET driver that is optimized for high

speed and high efficiency for driving both the upper and lower

(synchronous) MOSFETs of the buck converter.