IR3082M International Rectifier Corp., IR3082M Datasheet - Page 6

• Manufacturer Part Number: IR3082M
• Description: Xphasetm Amd Opterontm/athlon 64tm Control Ic
• Manufacturer: International Rectifier Corp.

SYSTEM THEORY OF OPERATION
XPhase
The XPhase
requiring small size, design flexibility, low voltage, high current, and fast transient response. The architecture can
be used in any multiphase converter ranging from 1 to 16 or more phases where flexibility facilitates the design
trade-off of multiphase converters. The scalable architecture can be applied to other applications which require
high current or multiple output voltages.
As shown in Figure 2, the XPhase
each using a single Phase IC. The Control IC communicates with the Phase ICs through a 5-wire analog bus, i.e.
bias voltage, phase timing, average current, error amplifier output, and VID voltage. The Control IC incorporates all
the system functions, i.e. VID, PWM ramp oscillator, error amplifier, bias voltage, and fault protections etc. The
Phase IC implements the functions required by the converter of each phase, i.e. the gate drivers, PWM comparator
and latch, over-voltage protection, and current sensing and sharing.
There is no unused or redundant silicon with the XPhase
controller that can be configured for 2, 3, or 4 phase operation. PCB Layout is easier since the 5 wire bus
eliminates the need for point-to-point wiring between the Control IC and each Phase. The critical gate drive and
current sense connections are short and local to the Phase ICs. This improves the PCB layout by lowering the
parasitic inductance of the gate drive circuits and reducing the noise of the current sense signal.
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ENABLE
TM
12V
VID0
VID1
VID2
VID3
VID4
Architecture
TM
architecture is designed for multiphase interleaved buck converters which are used in applications
IR3082
CONTROL
IC
>> BIAS VOLTAGE
>> PHASE TIMING
<< CURRENT SENSE
>> PWM CONTROL
>> VID VOLTAGE
TM
CONTROL BUS
architecture consists of a Control IC and a scalable array of phase converters
Figure 2 – System Block Diagram
CURRENT SHARE
CURRENT SHARE
ADDITIONAL PHASES
IR3086
PHASE
IC
IR3086
PHASE
IC
TM
architecture compared to others such as a 4 phase
CCS
CCS
RCS
RCS
INPUT/OUTPUT
CIN
COUT
POWER GOOD
VR HOT
PHASE FAULT
12/17/04
+SEN
VDD_CORE
GND
-SEN
IR3082