Features and Benefits

  • ±2% DC Accuracy
  • 0.1% (typ) DC Load Regulation
  • Adjustable Switching Frequency to 350kHz
  • Idle Mode™ Pulse-Skipping Operation
  • 1.10V to 5.5V Adjustable Output Voltage
  • 3.15V Minimum IC Supply Voltage (at VCC pin)
  • Internal Digital Soft-Start
  • 1.1V ±2% Reference Output
  • 1µA Total Shutdown Current
  • Output Overvoltage Crowbar Protection
  • Output Undervoltage Shutdown (foldback)
  • Tiny 16-Pin QSOP Package

Product Details

The MAX1637 synchronous, buck, switch-mode power-supply controller generates the CPU supply voltage in battery-powered systems. The MAX1637 is a stripped-down version of the MAX1636 in a smaller 16-pin QSOP package. The MAX1637 is intended to be powered separately from the battery by an external bias supply (typically the +5V system supply) in applications where the battery exceeds 5.5V. The MAX1637 achieves excellent DC and AC output voltage accuracy. This device can operate from a low input voltage (3.15V) and delivers the excellent load-transient response needed by upcoming generations of dynamic-clock CPUs.

Using synchronous rectification, the MAX1637 achieves up to 95% efficiency. Efficiency is greater than 80% over a 1000:1 load-current range, which extends battery life in system-suspend or standby mode. Excellent dynamic response corrects output load transients caused by the latest dynamic-clock CPUs within five 300kHz clock cycles. Powerful 1A on-board gate drivers ensure fast external N-channel MOSFET switching.

The MAX1637 features a logic-controlled and synchronizable, fixed-frequency, pulse-width-modulation (PWM) operating mode. This reduces noise and RF interference in sensitive mobile-communications and pen-entry applications. Asserting the SKIP-bar pin enables fixed-frequency mode, for lowest noise under all load conditions. For a stand-alone device that includes a +5V VL linear regulator and low-dropout capabilities, refer to the MAX1636 data sheet.


  • Handy-Terminals, PDAs
  • Notebook Computers
  • Subnotebook Computers

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Product Recommendations

MAX1637 Companion Parts

Recommended Related Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

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List Pricing

(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.


Lead Times

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