19-4815; Rev 3; 3/11
Low-Cost, 3A, 4.5V to 28V Input, 350kHz, PWM
Step-Down DC-DC Regulator with Internal Switches
The MAX15041 low-cost, synchronous DC-DC convert-
er with internal switches delivers an output current up to
3A. The MAX15041 operates from an input voltage of
4.5V to 28V and provides an adjustable output voltage
from 0.6V to 90% of V
, set with two external resistors.
The MAX15041 is ideal for distributed power systems,
preregulation, set-top boxes, television, and other con-
The MAX15041 features a peak-current-mode PWM con-
troller with internally fixed 350kHz switching frequency
and a 90% maximum duty cycle. The current-mode con-
trol architecture simplifies compensation design, and
ensures a cycle-by-cycle current limit and fast response
to line and load transients. A high-gain transconductance
error amplifier allows flexibility in setting the external com-
pensation by using a type II compensation scheme,
thereby allowing the use of all ceramic capacitors.
This synchronous buck regulator features internal
MOSFETs that provide better efficiency than asynchro-
nous solutions, while simplifying the design relative to
discrete controller solutions. In addition to simplifying
the design, the integrated MOSFETs minimize EMI,
reduce board space, and provide higher reliability by
minimizing the number of external components.
The MAX15041 also features thermal shutdown and
overcurrent protection (high-side sourcing and low-side
sinking), and an internal 5V LDO with undervoltage
lockout. In addition, this device ensures safe startup
when powering into a prebiased output.
Other features include an externally adjustable soft-start
that gradually ramps up the output voltage and reduces
inrush current. Independent enable control and power-
good signals allow for flexible power sequencing.
The MAX15041 is available in a space-saving, high-
power, 3mm x 3mm, 16-pin TQFN-EP package and is
fully specified from -40°C to +85°C.
Distributed Power Systems
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
o Up to 3A of Continuous Output Current
o ±1% Output Accuracy Over Temperature
o 4.5V to 28V Input Voltage Range
o Adjustable Output Voltage Range from 0.606V to
0.9 x V
o Internal 170mΩ R
High-Side and 105mΩ
Low-Side Power Switches
o Fixed 350kHz Switching Frequency
o Up to 93% Efficiency
o Cycle-By-Cycle Overcurrent Protection
o Programmable Soft-Start
o Stable with Low-ESR Ceramic Output Capacitors
o Safe Startup into Prebiased Output
o Enable Input and Power-Good Output
o Fully Protected Against Overcurrent and
LDO Undervoltage Lockout
o Space-Saving, Thermally Enhanced, 3mm x 3mm
-40°C to +85°C 16 TQFN-EP*
+ Denotes a lead(Pb)-free/RoHS-compliant package.
* EP = Exposed pad.
Typical Operating Circuit
1.8V AT 3A