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FEATURES
ADOPT™ Optimal Positioning Technology for Superior
Load Transient Response and Fewest Output Capacitors
Complies with VRM 9.0 with Lowest System Cost
Active Current Balancing between Both Output Phases
5-Bit Digitally Programmable 1.1 V to 1.85 V Output
Dual Logic-Level PWM Outputs for Interface to External
High Power Drivers
Total Output Accuracy ؎0.8% over Temperature
Current-Mode Operation
Short Circuit Protection
Power Good Output
Overvoltage Protection Crowbar Protects
Microprocessors with No Additional
External Components
APPLICATIONS
Desktop PC Power Supplies for:
Intel Pentium® 4 Processors
AMD Athlon™ Processors
VRM Modules
5-Bit Programmable 2-Phase
Synchronous Buck Controller
ADP3160/ADP3167
FUNCTIONAL BLOCK DIAGRAM
VCC
SET
UVLO
AND
BIAS
PWM1
RESET
CROWBAR
REF
3.0V
REFERENCE
2-PHASE
DRIVER
LOGIC
PWM2
CMP3
GND
DAC+24%
PWRGD
CT
OSCILLATOR
CMP
CMP2
DAC–18%
CS–
CMP
CS+
CMP1
COMP
gm
ADP3160/ADP3167
FB
VID
DAC
VID4
GENERAL DESCRIPTION
The ADP3160 and ADP3167 are highly efficient, dual output,
synchronous buck switching regulator controllers optimized for
converting a 5 V or 12 V main supply into the core supply voltage
required by high-performance processors, such as Pentium 4 and
Athlon. The ADP3160 uses an internal 5-bit DAC to read a voltage identification (VID) code directly from the processor that is
used to set the output voltage between 1.1 V and 1.85 V. The
devices use a current-mode PWM architecture to drive two logiclevel outputs at a programmable switching frequency that can be
optimized for VRM size and efficiency. The output signals are
180 degrees out of phase, allowing for the construction of two
complementary buck switching stages. These two stages share the
dc output current to reduce overall output voltage ripple. An
active current balancing function ensures that both phases carry
equal portions of the total load current, even under large transient
loads, to minimize the size of the inductors. The ADP3160 control
VID3
VID2
VID1
VID0
loop has been optimized for conversion from 12 V, while the
ADP3167 is designed for conversion from a 5 V supply.
The ADP3160 and ADP3167 also use a unique supplemental
regulation technique called active voltage positioning to enhance
load transient performance. Active voltage positioning results
in a dc/dc converter that meets the stringent output voltage
specifications for high-performance processors, with the minimum
number of output capacitors and smallest footprint. Unlike
voltage-mode and standard current-mode architectures, active
voltage positioning adjusts the output voltage as a function of
the load current so that it is always optimally positioned for a
system transient. They also provide accurate and reliable short
circuit protection and adjustable current limiting.
The ADP3160 is specified over the commercial temperature
range of 0∞C to 70∞C and is available in a 16-lead narrow body
SOIC package.
ADOPT is a trademark of Analog Devices, Inc.
Athlon is a trademark of Advanced Micro Devices, Inc.
Pentium is a registered trademark of Intel Corporation.
REV. B
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2002
