US3011 Datasheet, PDF (1/11 Pages) UNISEM – 5 BIT PROGRAMMABLE SYNCHRONOUS BUCK CONTROLLER IC

US3011
5 BIT PROGRAMMABLE SYNCHRONOUS BUCK
FEATURES
CONTROLLER IC
PRELIMINARY DATASHEET
DESCRIPTION
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
APPLICATIONS
Pentium III & Pentium II™ processor DC to DC con-
verter application
Low cost Pentium with AGP
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.
TYPICAL APPLICATION
L1
Q1
5V
C5
R1
C1
C3
R2
L2
C8
Q2
R4
R3
C10
12V
C2
VID4
VID3
VID2
VID1
VID0
C6
D1
C4
18
2
V12 CS+
11 NC/Gnd
3 SS
D4
D3
8
7
14
HDrv
D2
6
15
13
NC/ CS-
Boot
US3011
D1
D0
5
4
17
LDrv
Ct/Rt
20
16
1
Gnd NC/Sen
Vfb 10
R5
V5/Comp 9
OVP PGd
19
12
C9
C7
C11
R9
R7
C12
R8
C13
R6
C14
3011app1-1.1
Power Good
OVP
Notes: Pentium II and Pentium III are
trade marks of Intel Corp.
PACKAGE ORDER INFORMATION
Ta (°C) Device
0 TO 70 US3011CW
Package
20 pin Plastic SOIC WB
VID Voltage Range
1.3V to 3.5V
Rev. 1.3
12/8/00
4-1