IR3505 Datasheet, PDF (1/19 Pages) International Rectifier – XPHASE3TM PHASE IC

IR3505
DATA SHEET
XPHASE3^TM PHASE IC
DESCRIPTION
The IR3505 Phase IC combined with an IR XPhase3^TM Control IC provides a full featured and flexible way to
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^TM architecture results in a power supply that is smaller, less
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
12V
CCS
RCS
6 Wire
Bus to
Control
IC
1 _ISHARE
SW ¹²
2
3
IR3505
DACIN
GATEH
PHASE
LGND _IC
BOOST
11
10
CBST
4 _PHSIN
VCCL ⁹
VCCL
Page 1 of 19
CVCCL
CIN
L
VOUT+
COUT
VOUT-
Mar 04^th, 2008