IRU3046 Datasheet, PDF (1/20 Pages) International Rectifier – DUAL SYNCHRONOUS PWM CONTROLLER WITH CURRENT SHARING CIRCUITRY AND LDO CONTROLLER

Data Sheet No. PD94251
IRU3046
DUAL SYNCHRONOUS PWM CONTROLLER WITH
CURRENT SHARING CIRCUITRY AND LDO CONTROLLER
PRELIMINARY DATA SHEET
FEATURES
DESCRIPTION
Dual Synchronous Controller in 24-Pin Package
with 1808 out-of-phase operation
LDO Controller with Independent Bias Supply
Can be configured as 2-Independent or 2-Phase
PWM Controller
Programmable Current Sharing in 2-Phase Configu-
ration
Flexible, Same or Separate Supply Operation
Operation from 4V to 25V Input
Programmable Switching Frequency up to 400KHz
Soft-Start controls all outputs
Precision Reference Voltage Available
500mA Peak Output Drive Capability
Short Circuit Protection for all outputs
Power Good Output
Synchronizable with External Clock
The IRU3046 IC combines a Dual synchronous Buck
controller and a linear regulator controller, providing a
cost-effective, high performance and flexible solution for
multi-output applications. The Dual synchronous con-
troller can be configured as 2-independent or 2-phase
controller. In 2-phase configuration, the IRU3046 provides
a programmable current sharing which is ideal when the
output power exceeds any single input power budget.
IRU3046 provides a separate adjustable output by driv-
ing a switch as a linear regulator. This device features
programmable switching frequency up to 400KHz per
phase, under-voltage lockout for all input supplies, an
external programmable soft-start function as well as out-
put under-voltage detection that latches off the device
when an output short is detected.
APPLICATIONS
Dual-Phase Power Supply
DDR Memory Source Sink Vtt Application
Graphic Card
Hard Disk Drive
Power supplies requiring multiple outputs
TYPICAL APPLICATION
12V
5V
C1
L1
C2
3.3V
C6
VOUT2
C5
Q1
R1
C7
R2
C3
C4
C13
VCL VcH1 VcH2
HDrv1
Vcc
VccLDO
V SEN33
LDrv1
C8 ^R3
V OUT3
Fb3
U1
PGnd
V REF
Rt ^IRU3046 Vp2
Sync
Fb1
Comp1
Fb2
C9 ^R4
Comp2
HDrv2
PGood
PGood
SS
C10
LDrv2
Gnd
D1
C12
L2
D2
C11
Q2
C14
L3
R5
Q3
C15
R6
Q4
C17
L4
R9
Q5
C18
R10
VOUT1
C16
R7
R8
Figure 1 - Typical application of IRU3046 configured as 2-phase converter with current sharing.
PACKAGE ORDER INFORMATION
TA (°C)
DEVICE
0 To 70 IRU3046CF
PACKAGE
24-Pin Plastic TSSOP (F)
FREQUENCY
200-400KHz
Rev. 1.9
09/27/02
www.irf.com
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