IRU3073 Datasheet, PDF (1/21 Pages) International Rectifier – SYNCHRONOUS PWM CONTROLLER WITH OVER-CURRENT PROTECTION / LDO CONTROLLER

Data Sheet No. PD94699
IRU3073
SYNCHRONOUS PWM CONTROLLER WITH
OVER-CURRENT PROTECTION / LDO CONTROLLER
FEATURES
Synchronous Controller plus one LDO controller
Current Limit using MOSFET Sensing
Single 5V/12V Supply Operation
Programmable Switching Frequency up to
400KHz
Soft-Start Function
Fixed Frequency Voltage Mode
Precision Reference Voltage Available
Uncommitted Error Amplifier available for DDR
voltage tracking application
APPLICATIONS
DDR memory source sink VTT application
Low cost on-board DC to DC such as
12V/5V to output voltages as low as 0.8V
Graphic Card
Hard Disk Drive
Multi-Output Applications
DESCRIPTION
The IRU3073 controller IC is designed to provide a low
cost synchronous Buck regulator for on-board DC to DC
converter for multiple output applications.
The outputs can be programmed as low as 0.8V for low
voltage applications.
Selectable over-current protection is provided by using
external MOSFET's on-resistance for optimum cost and
performance.
This device features a programmable frequency set from
200KHz to 400KHz, under-voltage lockout for all input
supplies, an external programmable soft-start function
as well as output under-voltage detection that latches
off the device when an output short is detected.
TYPICAL APPLICATION
3.3V
VOUT2
Q1
C2
R1
R2
C3
0.1uF
C4
R8 _C9
R9
C11
Vcc
Drv2
Fb2
VcH
U1 ^VcL
IRU3073
HDrv
VP1
VREF
Comp
Rt
SS/SD
Gnd
OCSet
LDrv
Fb1
PGnd
C1
D1
R7
R10
R11
12V
L1
+5V
C6
C7
Q4
L2
VOUT1
Q5
C10
Figure 1 - Typical application of IRU3073.
PACKAGE ORDER INFORMATION
TA (°C)
0 To 70
DEVICE
IRU3073CQ
PACKAGE
16-Pin Plastic QSOP NB (Q)
Rev. 1.0
09/17/03
www.irf.com
1