Data Sheet No. PD94249
IRU3013
VRM 8.5 COMPATIBLE
5-BIT PROGRAMMABLE SYNCHRONOUS BUCK
CONTROLLER IC WITH TRIPLE LDO CONTROLLER
DESCRIPTION
The IRU3013 controller IC is specifically designed for
Intel Pentium III錚?microprocessor applications as de-
scribed in the VRM 8.5 specification.
The IC provides
a single chip solution for the Vcore, 1.2V AGTL+,
1.8V and a third uncommitted LDO controller that
can be used either as 1.2V power good detector or
to provide 1.5V AGP bus in applications that this
voltage is required.
The IRU3013 features a patented
topology that, in combination with a few external com-
ponents, (*Note: See application current in figure 3) will
provide in excess of 30A of output current for an on-
board Vcore synchronous converter while automatically
providing the output voltage specified in VRM 8.5 speci-
fication. The IRU3013 also features,
loss-less current
sensing by using the R
DS(ON)
of the high side Power
MOSFET as the sensing resistor,
a Power Good win-
dow comparator that switches its open collector output
low when the output is outside of a
鹵10%
window. Other
features of the device are: Under-voltage lockout for both
5V and 12V supplies, an external programmable soft-
start function, and the ability to program the oscillator
frequency by connecting an external capacitor.
FEATURES
Meets Latest VRM 8.5 Specification
Provides Single Chip Solution for Vcore, 1.2V AGTL+,
1.8V and V
DDQ
On-Board 5-Bit DAC and Decoder programs the out-
put voltage from 1.050V to 1.825V
Loss-less Short Circuit Protection
Synchronous operation allows maximum efficiency
Patented architecture allows fixed frequency opera-
tion as well as 100% duty cycle when operating with
a changing load
Minimum Part Count, No External Compensation
Soft-Start
High current totem pole driver for directly driving an
external Power MOSFET
Power Good Function
APPLICATIONS
Pentium III with VRM 8.5 Specification
DC to DC Converters
TYPICAL APPLICATION
3.3V
LINEAR
CONTROL
VRM 8.5 VID
5V
V
OUT
2
SWITCHER
CONTROL
V
OUT
1
IRU3013
LINEAR
CONTROL
LINEAR
CONTROL
V
OUT
3
V
OUT
4
Figure 1 - Typical application of IRU3013.
Note:
Pentium III is trade mark of Intel Corp.
PACKAGE ORDER INFORMATION
T
A
(擄C)
0 To 70
0 To 70
Rev. 1.2
09/06/01
DEVICE
IRU3013CW
IRU3013CQ
PACKAGE
24-Pin Plastic SOIC WB
24-Pin Plastic QSOP
1
1
2
3
4
5
6
