IRU3055 Datasheet, PDF (1/26 Pages) International Rectifier – 5-BIT PROGRAMMABLE 3-PHASE SYNCHRONOUS BUCK CONTROLLER IC

Data Sheet No. PD94262
IRU3055
5-BIT PROGRAMMABLE 3-PHASE
SYNCHRONOUS BUCK CONTROLLER IC
PRELIMINARY DATA SHEET TEST SPEC
FEATURES
DESCRIPTION
Meets VRM 9.0 Specification
3-Phase Controller with On-Board MOSFET Driver
On-Board DAC programs the output voltage from
1.075V to 1.850V
Loss-less Short Circuit Protection
Programmable Frequency
Synchronous operation allows maximum efficiency
Minimum Part Count
Soft-Start
Power Good Function
Hiccup Mode Current Limit
APPLICATIONS
The IRU3055 is a 3-phase synchronous Buck controller
which provides high performance DC to DC converter for
high current applications.
The IRU3055 controller IC is specifically designed to meet
Intel and AMD specifications for the new microproces-
sor requiring low voltage and high current.
The IRU3055 features under-voltage lockout for both 5V
and 12V supplies, an external and programmable soft-
start function as well as programming the oscillator fre-
quency by using an external resistor.
Intel Pentium 4 and AMD K7
TYPICAL APPLICATION
C1
1uF
5V
Vcc
C5
1uF
Ref
Rt
V CL1
V CL23
HDrv1
OCSet
LDrv1
PGnd1/
OCGnd
CS1
C9
R3
1uF
47K
SS
C10
0.1uF
D4
D3
D2
D1
HDrv2
IRU3055
LDrv2
PGnd2
CS2
HDrv3
C12 ^R6
22nF _27K
C7
100pF
(Optional)
D0
Comp
LDrv3
PGnd3
CS3
Fb
R1
2.2K
D1
C3
1uF
L1
C2
1uH
0.1uF
C4
1000uF
Q1
IRF3704S
Q2
IRF3711S
Q3
IRF3704S
Q4
IRF3711S
Q5
IRF3704S
Q6
IRF3711S
C6
6x 1500uF
L2
R2
1.5K
1uH
C8
1uF
L3
R4
1.5K
1uH
C11
1uF
L4
R5
1.5K
1uH
C13
1uF
Figure 1 - Typical application of IRU3055.
12V
1.5V / 60A
C14
8x 2700uF
PACKAGE ORDER INFORMATION
TA (8C)
0 To 70
DEVICE
IRU3055CQ
PACKAGE
36-Pin Plastic QSOP WB (Q)
Rev. 1.4
08/13/02
www.irf.com
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