1. Products
  2. Power Monitor, Control, and Protection
  3. Supervisory Circuits
  4. Triple-Supply Monitors
  5. LTC1728


Features and Benefits

  • Monitors Three Inputs Simultaneously
    • LTC1727-5: 5V, 3.3V and ADJ
    • LTC1727-2.5: 2.5V, 3.3V and ADJ
    • LTC1728-5: 5V, 3.3V and ADJ
    • LTC1728-2.5: 2.5V, 3.3V and ADJ
    • LTC1728-1.8: 3V, 1.8V and ADJ
    • LTC1728-3.3: 3.3V, 1.8V and ADJ
  • ±1.5% Threshold Accuracy Over Temperature
  • Very Low Supply Current: 10µA Typ
  • 200ms Reset Time Delay
  • Active Low RESET Output
  • Power Supply Glitch Immunity
  • Guaranteed RESET for VCC3 ≥ 1V or VCC5/VCC25/VCC18 ≥ 1V
  • LTC1727 Includes Monitor Output for Each Supply
  • LTC1727: 8-Lead MSOP and SO Packages
  • LTC1728: 5-Lead SOT-23 Package

Product Details

The LTC1727 is a triple supply monitor intended for systems with multiple supply voltages. Each supply monitor has its own open-drain output for individual supply monitoring. A common open-drain reset output remains low until all three supplies have been in compliance for 200ms. Tight 1.5% accuracy specifications and glitch immunity ensure reliable reset operation without false triggering.

The LTC1728 is functionally identical to the LTC1727 without the individual monitor outputs.

The RST output is guaranteed to be in the correct state for VCC5/VCC25/VCC18 or VCC3 down to 1V. The LTC1727/LTC1728 may also be configured to monitor any one or two VCC inputs instead of three, depending on system requirements.

Very low (10µA typical) supply current makes the LTC1727/LTC1728 ideal for power conscious systems.

The LTC1727 is available in an 8-lead MSOP or SO package and the LTC1728 is available in a 5-lead SOT-23 package.


  • Desktop Computers
  • Notebook Computers
  • Intelligent Instruments
  • Portable Battery-Powered Equipment
  • Network Servers

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.

Tools & Simulations


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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.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LTC1728ES5-1.8#TRMPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-1.8#TRPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-2.5#TRMPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-2.5#TRPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-3.3#TRMPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-3.3#TRPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-5#TRMPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728ES5-5#TRPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728HS5-5#TRMPBF Material Declaration Reliability Data 5-Lead TSOT-23
LTC1728HS5-5#TRPBF Material Declaration Reliability Data 5-Lead TSOT-23
Wafer Fabrication Data R413 Reliability Data

Sample & Buy

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Buy Now Pricing

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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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