±9-0725; Rev 0; 8/07
Dual, 3A, 2MHz Step-Down Regulator
MAX83
General Description
The MAX8833 high-efficiency, dual step-down regulator
is capable of delivering up to 3A at each output. The
device operates from a 2.35V to 3.6V supply, and pro-
vides output voltages from 0.6V to 0.9 x V , making it
IN
ideal for on-board point-of-load applications. Total output
error is less than ±±1 over load, line, and temperature.
Features
o 35mΩ On-Resistance Internal MOSFETs
o Dual, 3A, PWM Step-Down Regulators
o Fully Protected Against Overcurrent,
Short Circuit, and Overtemperature
o ±±1 Output Accuracy over ꢀoad, ꢀine,
and Temperature
The MAX8833 operates in PWM mode with a switching
frequency ranging from 0.5MHz to 2MHz, set by an
external resistor. It can also be synchronized to an
external clock in the same frequency range. Two inter-
nal switching regulators operate ±80° out-of-phase to
reduce the input ripple current, and consequently
reduce the required input capacitance. The high
operating frequency minimizes the size of external
components. High efficiency, internal dual-nMOS
design keeps the board cool under heavy loads. The
voltage-mode control architecture and the high-band-
width (> ±5MHz typ) voltage-error amplifier allow a type
III compensation scheme to be utilized to achieve fast
response under both line and load transients, and also
allow for ceramic output capacitors.
o Operates from 2.35V to 3.6V Supply
o REFIN on One Channel for Tracking or
External Reference
o Integrated Boost Diodes
o Adjustable Output from 0.6V to 0.9 x VIN
o Soft-Start Reduces Inrush Supply Current
o 0.5MHz to 2MHz Adjustable Switching,
or FSYNC Input
o All-Ceramic-Capacitor Design
o ±80° Out-of-Phase Operation Reduces Input
Ripple Current
o Individual Enable Inputs and PWRGD Outputs
o Available in 5mm x 5mm Thin QFN Package
Programmable soft-start reduces input inrush current.
Two enable inputs allow the turning on/off of each out-
put individually, resulting in great flexibility for system-
level designs. A reference input is provided to facilitate
output-voltage tracking applications. The MAX8833 is
available in a 32-pin thin QFN (5mm x 5mm) package
with 0.8mm max height.
Ordering Information
PART
PIN-PACKAGE
PKG CODE
32 Thin QFN
(5mm x 5mm)
MAX8833ETJ+
T3255-4
Note: The device is specified over the -40°C to +85°C extended
temperature range.
Applications
+Denotes a lead-free package.
ASIC/CPU/DSP Power Supplies
Typical Operating Circuit
DDR Power Supplies
INPUT2
INPUT1
Set-Top Box Power Supplies
Printer Power Supplies
Network Power Supplies
2.35V TO 3.6V
2.35V TO 3.6V
IN1 IN2
BST1
BST2
OUTPUT1
1.2V / 3A
OUTPUT2
1.5V / 3A
LX1
LX2
PGND1
PGND2
MAX8833
FB2
FB1
COMP1
COMP2
TYPE III
TYPE III
COMPENSATION
COMPENSATION
PWRGD1 PWRGD2
EN1 EN2
ON
ON
GND
OFF
OFF
Pin Configuration appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
±
For pricing, delivery, and ordering information, please contact Maxim Direct at ±-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.