Alternative Parts


Features and Benefits

  • Selects Highest Priority Valid Supply from Two Inputs
  • Wide 1.8V to 18V Operating Range
  • Internal Dual 2Ω, 0.5A Switches
  • Low 3.6µA Operating Current
  • Low 320nA V2 Current When V1 Connected to OUT
  • Blocks Reverse and Cross Conduction Currents
  • Reverse Supply Protection to –15V
  • Built-In V2 Test with Optional V2 Disconnect
  • V2 Freshness Seal/Ship Mode
  • ±1.5% Accurate Adjustable Switchover Threshold
  • ±2.3% Accurate V2 Monitor and Comparator
  • Overcurrent and Thermal Protection
  • Thermally Enhanced 12-Pin 3mm × 3mm DFN and 12-Lead Exposed Pad MSOP Packages

Product Details

The LTC4420 is a dual input monolithic PowerPath prioritizer, with low operating current, that provides backup switchover for keeping critical circuitry alive during brownout and power loss conditions. Unlike diode-OR products, little current is drawn from the inactive supply even if its voltage is greater than the active supply.

Internal 2Ω, current limited PMOS switches provide power path selection from a primary input (V1) or a backup input (V2) to the output. Two adjustable voltage monitors set via external resistive dividers provide flexibility in setting V1 to V2 switchover and V2 undervoltage thresholds. V1 is monitored continuously while V2 supply monitoring includes controllable low duty cycle UV monitoring. When primary input V1 drops, the ADJ monitor causes OUT to be switched to V2. When V2 drops, it is disconnected from OUT if V2DIS is low. Fast non-overlap switchover circuitry prevents reverse and cross conduction while minimizing output droop.

Auxiliary voltage monitor CMP1 provides flexible voltage monitoring and output V2OK provides V2 undervoltage status. Freshness seal mode prevents V2 battery discharge during storage or shipment.


  • Low Power Battery Backup
  • Portable Equipment
  • Point-of-Sale (POS) Equipment

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (1)

Tools & Simulations


LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.


Models for the following parts are available in LTspice:


Product Recommendations

LTC4420 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.

PCN-PDN Information

Sample & Buy

The USA 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. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

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Evaluation Boards

Pricing displayed is based on 1-piece.

Up to two boards can be purchased through To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.