Features and Benefits

  • Two Low Voltage Adjustable Inputs (0.5V)
  • Pin Selectable Input Polarity Allows Negative and OV Monitoring
  • Guaranteed Threshold Accuracy: ±1.5%
  • 6.5V Shunt Regulator for High Voltage Operation
  • Low 50μA Quiescent Current
  • Buffered 1V Reference for Negative Supply Offset
  • Input Glitch Rejection
  • Adjustable Reset Timeout Period
  • Selectable Internal Timeout Saves Components
  • Open-Drain RST Output
  • Accurate UVLO for 2.5V, 3.3V, 5V Systems
  • Ultralow Voltage Reset: VCC = 0.5V Guaranteed
  • Space Saving 8-Lead TSOT-23 and 3mm × 2mm DFN Packages

Product Details

The LTC2909 is a dual input monitor intended for a variety of system monitoring applications. Polarity selection and a buffered reference output allow the LTC2909 to monitor positive and negative supplies for undervoltage (UV) and overvoltage (OV) conditions.

The two inputs have a nominal 0.5V threshold, featuring tight 1.5% threshold accuracy over the entire operating temperature range. Glitch filtering ensures reliable reset operation without false triggering. A third fixed-threshold UVLO monitor on the part’s VCC (also 1.5% accuracy) is available for standard logic supplies.

The common reset output has a timeout that may use a preset 200ms, be set by an external capacitor or be disabled. A three-state input pin sets the input polarity of each adjustable input without requiring any external components.

The LTC2909 provides a highly versatile, precise, space-conscious, micropower solution for supply monitoring.


  • Desktop and Notebook Computers
  • Handheld Devices
  • Network Servers
  • Core, I/O Monitor
  • Automotive

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


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:


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.

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.

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.

Price Table Help