19-2745; Rev 1; 9/03
Dual-Phase, Quick-PWM Controller for
AMD Hammer CPU Core Power Supplies
General Description
Features
The MAX1544 is a dual-phase, Quick-PWM™, step-
down controller for AMD Hammer™ CPU core supplies.
Dual-phase operation reduces input ripple current
requirements and output voltage ripple while easing
component selection and layout difficulties. The Quick-
PWM control scheme provides instantaneous response
to fast load-current steps. The MAX1544 includes active
voltage positioning with adjustable gain and offset,
reducing power dissipation and bulk output capacitance
requirements.
o Dual-Phase, Quick-PWM Controller
o ±±0.75 ꢀ Accuracy Over Line, Load, and
OUT
Temperature (103ꢀ)
o Active ꢀoltage Positioning with Adjustable Gain
and Offset
o 7-Bit On-Board DAC: ±06.7ꢀ to 1077ꢀ Output
Adjust Range
o Selectable 1±±kHz/2±±kHz/3±±kHz/77±kHz
Switching Frequency
The MAX1544 is intended for two different notebook CPU
core applications: stepping down the battery directly or
stepping down the 5V system supply to create the core
voltage. The single-stage conversion method allows this
device to directly step down high-voltage batteries for the
highest possible efficiency. Alternatively, two-stage con-
version (stepping down the 5V system supply instead of
the battery) at a higher switching frequency provides the
minimum possible physical size.
o 4ꢀ to 28ꢀ Battery Input ꢀoltage Range
o Adjustable Slew-Rate Control
o Drives Large Synchronous Rectifier MOSFETs
o Selectable Output Overvoltage Protection
o Undervoltage and Thermal-Fault Protection
o Power Sequencing and Timing
o Selectable Suspend ꢀoltage
The MAX1544 complies with AMD’s desktop and
mobile CPU specifications. The switching regulator fea-
tures soft-start and power-up sequencing, and
soft-shutdown. The MAX1544 also features indepen-
dent four-level logic inputs for setting the suspend volt-
age (S0–S1).
o Soft-Shutdown
o Selectable Single- or Dual-Phase Pulse Skipping
Ordering Information
The MAX1544 includes output undervoltage protection,
thermal protection, and voltage regulator power-OK
(VROK) output. When any of these protection features
detect a fault, the controller shuts down. Additionally, the
MAX1544 includes selectable overvoltage protection.
PART
TEMP RANGE
PIN-PACKAGE
MAX1544ETL -40°C to +100°C 40 Thin QFN 6mm ✕ 6mm
Pin Configuration
The MAX1544 is available in a low-profile, 40-pin 6mm
x 6mm thin QFN package. For other CPU platforms,
refer to the pin-to-pin compatible MAX1519/MAX1545
and MAX1532/MAX1546/MAX1547 data sheets.
TOP VIEW
TIME
TON
SUS
S0
1
2
30
V
DD
Applications
AMD Hammer Desktop or Notebook PCs
29 DLM
28 DHM
27 LXM
26 BSTM
25 VROK
24 D0
3
4
Multiphase CPU Core Supply
S1
5
MAX1544
SHDN
OFS
REF
6
Voltage-Positioned Step-Down Converters
Servers/Desktop Computers
7
D1
8
23
ILIM
9
22 D2
21 D3
10
V
CC
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
Hammer is a trademark of AMD.
THIN QFN
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.