IR3505

Page 1 of 19

Mar 04

DATA SHEET

XPHASE3

DESCRIPTION

The IR3505 Phase IC combined with an IR XPhase3

implement power solutions for the latest high performance CPUs and ASICs. The “Control” IC provides

overall system control and interfaces with any number of “Phase” ICs which each drive and monitor a single

phase of a multiphase converter. The XPhase3

expensive, and easier to design while providing higher efficiency than conventional approaches.

FEATURES

•

7V/2A gate drivers (4A GATEL sink current)

•

Support converter output voltage up to 5.1 V (Limited to VCCL-1.4V)

•

Support loss-less inductor current sensing

•

Feed-forward voltage mode control

•

Integrated boot-strap synchronous PFET

•

Only four IC related external components per phase

•

3 wire analog bus connects Control and Phase ICs (VDAC, Error Amp, ISHARE)

•

3 wire digital bus for accurate daisy-chain phase timing control without external components

•

Debugging function isolates phase IC from the converter

•

Self-calibration of PWM ramp, current sense amplifier, and current share amplifier

•

Single-wire bidirectional average current sharing

•

Small thermally enhanced 16L 3 x 3mm MLPQ package

•

RoHS compliant

APPLICATION CIRCUIT

CCS

ISHARE

1

SW

12

GATEH

11

BOOST

10

DACIN

2

PHSIN

4

VCCL

9

LGND

3

IR3505

PHASE

IC

CVCCL

CBST

RCS

CIN

L

VOUT+

VOUT-

VCCL

12V

COUT

6 Wire

Bus to

Control

IC