US3007 Datasheet, PDF (1/15 Pages) UNISEM – 5 BIT PROGRAMMABLE SYNCHRONOUS BUCK PLUS NON SYNCHRONOUS , LDO CONTROLLER AND 200MmA LDO ON BOARD

US3007
5 BIT PROGRAMMABLE SYNCHRONOUS BUCK PLUS NON SYN-
CHRONOUS , LDO CONTROLLER AND 200MmA LDO ON BOARD
FEATURES
PRELIMINARY DATASHEET
DESCRIPTION
Provides Single Chip Solution for Vcore,
GTL+ ,Clock Supply & 3.3V Switcher on board
Second Switcher Provides Simple Control for
the On board 3.3V supply
200 mA On board LDO regulator
Designed to meet Intel VRM 8.2 and 8.3
specification for Pentium II™
On board DAC programs the output voltage
from 1.3V to 3.5V
Linear regulator controller on board for 1.5V
GTL+ supply
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
Minimum part count
Soft Start
High current totem pole driver for direct
driving of the external Power MOSFET
Power Good function Monitors all Outputs
OVP Circuitry Protects the Switcher Outputs
and generates a Fault output
Thermal Shutdown
APPLICATIONS
Total Power Soloution for Pentium II processor
application
The US3007 controller IC is specifically designed to meet
Intel specification for Pentium II™ microprocessor ap-
plications as well as the next generation of P6 family
processors. The US3007 provides a single chip con-
troller IC for the Vcore , LDO controller for GTL+
and an internal 200mA regulator for clock supply
which are required for the Pentium II applications.
It also contains a switching controller to convert 5V
to 3.3V regulator for an on board applications that
either uses AT type power supply or it is desired
not to rely on the ATX power supply’s 3.3V output.
These devices feature a patented topology that in com-
bination with a few external components as shown in
the typical application circuit ,will provide in excess of
14A of output current for an on- board DC/DC converter
while automatically providing the right output voltage via
the 5 bit internal DAC .The US3007 also features, loss
less current sensing for both switchers by using the
Rds-on of the high side Power MOSFET as the sens-
ing resistor, internal current limiting for the clock
supply, a Power Good window comparator that switches
its open collector output low when any one of the out-
puts is outside of a pre programmed window. Other fea-
tures of the device are ; Undervoltage lockout for both
5V and 12V supplies, an external programmable soft
start function , programming the oscillator frequency via
an external resistor, OVP circuitry for both switcher out-
puts and an internal thermal shutdown.
TYPICAL APPLICATION
5V
Vout2
SWITCHER2
CONTROL
US3007
SWITCHER1
CONTROL
Vout1
Vout3
LINEAR
CONTROL
LINEAR
REGULATOR
3007app3-1.0
Vout4
Notes: Pentium II and Pentium Pro are
trade marks of Intel Corp.
PACKAGE ORDER INFORMATION
Ta (°C)
0 TO 70
Device
US3007CW
Rev. 1.8
12/8/00
Package
28 pin Plastic SOIC WB
4-1