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5V/3.3V/3V Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC Converters

Low Supply Current, High-Efficiency Over Wide Load Range

Product Details

Key Features

Parametric specs for Step-Down Switching Regulators
VIN (V) (min) 4
VIN (V) (max) 11.5
VOUT1 (V) (min) 1.3
VOUT1 (V) (max) 11.5
IOUT1 (A) (max) 0.225
Switch Type Internal
Preset VOUT (V) 3.3
Output Adjust. Method Preset
Resistor
Power Good Signal Yes
# DC-DC Outputs 1
Package/Pins SOIC (N)/8
Budgetary
Price (See Notes)
4.02
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Simplified Block Diagram

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Parameters

Parametric specs for Step-Down Switching Regulators
VIN (V) (min) 4
VIN (V) (max) 11.5
VOUT1 (V) (min) 1.3
VOUT1 (V) (max) 11.5
IOUT1 (A) (max) 0.225
Switch Type Internal
Preset VOUT (V) 3.3
Output Adjust. Method Preset
Resistor
Power Good Signal Yes
# DC-DC Outputs 1
Package/Pins SOIC (N)/8
Budgetary
Price (See Notes)
4.02

Key Features

  • High Efficiency for a Wide Range of Load Currents
  • 10µA Quiescent Current
  • Output Currents Up to 225mA
  • Preset or Adjustable Output Voltage:
    • 5.0V (MAX639)
    • 3.3V (MAX640)
    • 3.0V (MAX653)
  • Low-Battery Detection Comparator
  • Current-Limiting PFM Control Scheme

Applications/Uses

  • 5V to 3.3V Conversion
  • 9V Battery to 5V, 3.3V, or 3V Conversion
  • High-Efficiency Linear Regulator Replacement
  • Portable Instruments and Handy-Terminals

Description

The MAX639/MAX640/MAX653 step-down switching regulators provide high efficiency over a wide range of load currents, delivering up to 225mA. A current-limiting pulse-frequency-modulated (PFM) control scheme gives the devices the benefits of pulse-width-modulated (PWM) converters (high efficiency at heavy loads), while using only 10µA of supply current (vs. 2mA to 10mA for PWM converters). The result is high efficiency over a wide range of loads.

The MAX639/MAX640/MAX653 input range is 4V to 11.5V, and the devices provide lower preset output voltages of 5V, 3.3V, and 3V, respectively. Or, the output can be user-adjusted to any voltage from 1.3V to the input voltage.

The MAX639/MAX640/MAX653 have an internal 1A power MOSFET switch, making them ideal for minimum-component, low- and medium-power applications. For increased output drive capability, use the MAX649/MAX651/MAX652 step-down controllers, which drive an external P-channel FET to deliver up to 5W.

Simplified Block Diagram

MAX639, MAX640, MAX653: Typical Operating Circuit MAX639, MAX640, MAX653: Typical Operating Circuit Zoom icon

Technical Docs

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.