US3011
5 BIT PROGRAMMABLE SYNCHRONOUS BUCK
CONTROLLER IC
PRELIMINARY DATASHEET
FEATURES
Dual Layout Compatible with HIP6004A
Designed to meet Intel specification of VRM8.4
for Pentium III™
On board DAC programs the output voltage
from 1.3V to 3.5V. The US3011 remains on for
VID code of (11111).
Loss less Short Circuit Protection
Synchronous operation allows maximum
efficiency
Patented architecture allows fixed frequency
operation as well as 100% duty cycle during
dynamic load
Over Voltage Protection Output
Soft Start
High current totem pole driver for direct
driving of the external Power MOSFET
Power Good function
DESCRIPTION
The US3011controller IC is specifically designed to meet
Intel specification for latest Pentium III™ microproces-
sor applications as well as the next generation P6 fam-
ily processors. These products feature a patented topol-
ogy that in combination with a few external components
as shown in the typical application circuit ,will provide in
excess of 20A of output current for an on- board DC/DC
converter while automatically providing the right output
voltage via the 5 bit internal DAC.These devices also
features,
loss less current sensing by using the Rds-
on of the high side Power MOSFET as the sensing
resistor,
a Power Good window comparator that switches
its open collector output low when the output is outside
of a
±10%
window and an OVP output. Other features of
the device are ; Undervoltage lockout for both 5V and
12V supplies , an external programmable soft start func-
tion as well as programming the oscillator frequency by
using an external capacitor.
APPLICATIONS
Pentium III & Pentium II™ processor DC to DC con-
verter application
Low cost Pentium with AGP
TYPICAL APPLICATION
L1
L2
Q1
5V
C5
C1
C3
R2
R1
C8
Q2
R3
R4
C10
C6
C11
D1
C4
R7
18
V12
11 NC/Gnd
2
CS+
14
HDrv
15
NC/
Boot
13
CS-
17
LDrv
16
Gnd
1
NC/Sen
Vfb 10
R5
V5/Comp 9
D3
7
D2
6
D1
5
D0
4
Ct/Rt
20
OVP
19
PGd
12
C9
R6
R8
12V
R9
C12
C13
US3011
3 SS
C2
D4
8
VID4
VID3
VID2
VID1
VID0
C7
Power Good
C14
3011app1-1.1
OVP
Notes: Pentium II and Pentium III are
trade marks of Intel Corp.
PACKAGE ORDER INFORMATION
Ta (°C)
0 TO 70
Device
US3011CW
Package
20 pin Plastic SOIC WB
VID Voltage Range
1.3V to 3.5V
Rev. 1.3
12/8/00
4-1
UNISEM [ UNISEM ]
