4A, 2MHz Step-Down Regulator with Integrated Switches

Smallest, Most Efficient, 4A Step-Down Regulator Switches Frequencies Up to 2MHz


The MAX15038 high-efficiency switching regulator delivers up to 4A load current at output voltages from 0.6V to 90% of VIN. The IC operates from 2.9V to 5.5V, making it ideal for on-board point-of-load and postregulation applications. Total output error is less than ±1% over load, line, and temperature ranges.

The MAX15038 features fixed-frequency PWM mode operation with a switching frequency range of 500kHz to 2MHz set by an external resistor. The MAX15038 provides the option of operating in a skip mode to improve light-load efficiency. High-frequency operation allows for an all-ceramic capacitor design. The high operating frequency also allows for small-size external components.

The low-resistance on-chip nMOS switches ensure high efficiency at heavy loads while minimizing critical inductances, making the layout a much simpler task with respect to discrete solutions. Following a simple layout and footprint ensures first-pass success in new designs.

The MAX15038 comes with a high bandwidth (28MHz) voltage-error amplifier. The voltage-mode control architecture and the voltage-error amplifier permit a type III compensation scheme to be utilized to achieve maximum loop bandwidth, up to 20% of the switching frequency. High loop bandwidth provides fast transient response, resulting in less required output capacitance and allowing for all-ceramic-capacitor designs.

The MAX15038 provides two three-state logic inputs to select one of nine preset output voltages. The preset output voltages allow customers to achieve ±1% output-voltage accuracy without using expensive 0.1% resistors. In addition, the output voltage can be set to any customer value by either using two external resistors at the feedback with a 0.6V internal reference or applying an external reference voltage to the REFIN input. The MAX15038 offers programmable soft-start time using one capacitor to reduce input inrush current.
MAX15038: Typical Operating Circuit MAX15038: Typical Operating Circuit Enlarge+

Key Features

  • Internal 31mΩ RDS(ON) High-Side and 24mΩ RDS(ON) Low-Side MOSFETs
  • Continuous 4A Output Current Over Temperature
  • ±1% Output Accuracy Over Load, Line, and Temperature
  • Operates from 2.9V to 5.5V VIN Supply
  • Adjustable Output from 0.6V to (0.9 x VIN)
  • Soft-Start Reduces Inrush Supply Current
  • 500kHz to 2MHz Adjustable Switching Frequency
  • Compatible with Ceramic, Polymer, and Electrolytic Output Capacitors
  • Nine Preset and Adjustable Output Voltages
    • 0.6V, 0.7V, 0.8V, 1.0V, 1.2V, 1.5V, 1.8V, 2.0V, 2.5V, and Adjustable
  • Monotonic Startup for Safe-Start into Prebiased Outputs
  • Selectable Forced PWM or Skip Mode for Light Load Efficiency
  • Overcurrent and Overtemperature Protection
  • Output Current Sink/Source Capable with Cycle-by-Cycle Protection
  • Open-Drain Power-Good Output
  • Lead-Free, 4mm x 4mm, 24-Pin Thin QFN Package


  • ASIC/CPU/DSP Core and I/O Voltages
  • Base-Station Power Supplies
  • DDR Power Supplies
  • POLs
  • RAID Control Power Supplies
  • Server Power Supplies
  • Telecom and Networking Power Supplies
Part Number VIN
Preset VOUT
Output Adjust. Method IOUT1
Switch Type Synchronous Switching Power Good Signal DC-DC Outputs Oper. Freq.
Design Tools Package/Pins Budgetary
min max min max max See Notes
MAX15038  2.9 5.5 0.6 4.5
Dyn. REF In
4 Internal Yes Yes 1 2000 EE-Sim
$4.36 @1k
See All Step-Down Switching Regulators (312)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX15038EVKIT: Evaluation Kit for the MAX15038 and MAX15039

Technical Documents

Tutorial 5133 Power-Supply Solutions for Altera FPGAs
Tutorial 5132 Power-Supply Solutions for Xilinx FPGAs

Quality and Environmental Data

Product Reliability Reports: MAX15038.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Tools & Models

Design & Simulate MAX15038

Related Resources

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