IR3506 Datasheet, PDF (1/21 Pages) International Rectifier – XPHASE3TM DDR & VTT PHASE IC

IR3506
DATA SHEET
XPHASE3^TM DDR & VTT PHASE IC
DESCRIPTION
The IR3506 Phase IC combined with IR3522 xPHASE3^TM Control ICs implements a full featured DDR3 power
solution. The IR3522 provides control functions for both the VDDR and VTT power rails and interfaces with any
number of IR3506 Phase ICs each driving and monitoring a single phase to power any number of DDR3
DIMMs. The xPHASE3^TM architecture delivers a power supply that is smaller, more flexible, and easier to
design while providing higher efficiency than conventional approaches.
FEATURES
• Power State Indicator (PSI) interface provides the capability to maximize efficiency at light loads
• Anti-bias circuitry
• 7V/2A gate drivers (4A GATEL sink current)
• Support loss-less inductor current sensing
• Phase delay DFF bypassed during PSI assertion mode to improve output ripple performance
• Over-current protection during PSI assertion mode operation
• 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, IOUT)
• 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
• Soft-stop turn-off to insure VDDR and Vtt tracking
• Small thermally enhanced 16L 3 x 3mm MLPQ package
• RoHS Compliant
APPLICATION CIRCUIT
12V
CCS
RCS
7 Wire
Bus to
Control
IC
VCCL
Page 1 of 21
U1
U11
1 _IOUT
SW ¹²
2
3
IR3506
DACIN _PHASE GATEH
LGND _IC
BOOST
11
10
CBST
L
4 _PHSIN
VCCL ⁹
U12
CVCCL
CIN
VOUT+
COUT
VOUT-
V3.02