QTI Sensing Solutions


 A thermistor, or thermally sensitive resistor, is a resistor which changes resistance in response to a change in temperature. There are two basic types of thermistors, NTC or Negative Temperature Coefficient and PTC or Positive Temperature Coefficient thermistors. NTC thermistors exhibit a decrease in resistance when temperature rises. PTC thermistors exhibit an increase in resistance when temperature rises. 

About QTI Sensing Solutions

QTI Sensing Solutions, founded in 1977 as Quality Thermistor, Inc., was formed to meet the increasing demand for high quality electronic components for the aerospace industry. Since then, QTI has exceeded the requirements of some of the most stringent high cost of failure applications, changing the landscape of the supply chain for the entire industry.  Today, QTI Sensing Solutions continues to maintain its leadership position for mission-critical applications as well as for medical and industrial applications by supplying the world’s top companies with innovative products and services. In fact, QTI developed the highest standard for surface mount thermistors with the introduction of qualified surface mount parts to MIL-PRF-32192; supplying design engineers with fully qualified DSCC options for two PTC and three NTC surface mount package styles. Additionally, QTI has partnered with the NASA Goddard Space Flight Center for surface mount thermistors qualified to S311-P827, an industry first!  In addition to QTI’s accomplishments, our ISO:09001:2000 and AS9100 certified manufacturing and testing facilities in Idaho enhances our ability to meet the needs of today’s challenging temperature measurement and control applications.

Why Choose QTI's Temperature Sensors?

We are the experts in thermistor manufacturing.

  • We test 100% for accuracy.
  • We care about the details.
  • We provide design assistance.
  • We manufacture in the USA.
  • We are Quality Driven - https://www.thermistor.com/quality

Thermistor Sensors

 From fast responding miniature thermistors to molded plastic housings that help stabilize temperature fluctuations, QTI has a large selection of sensors to fit your application. 

 Whether you need a temperature probe for spot measurements or a permanently mounted sensor, QTI has your temperature sensing solution. 

 These sensors are available in a variety of styles and sizes to make measuring surface temperature easy. 

 Miniature and micro thermistors are ideal for a variety of applications, from human body temperature measurement to thermal profiling of electronics. 

 QTI's waterproof temperature sensors are ideal for applications with moisture or high humidity. 

 QTI’s Platinum Thin Film RTD sensors are manufactured with state of the art thin film Platinum RTD elements and materials designed to give superior temperature measurement and stability. 


 QTI's NTC thermistors are available in a variety of configurations to meet your needs.  Choose between surface mount or leaded parts. 

 The linear and proportional change in Resistance/Temperature that PTC thermistors display offers simplified and reliable thermal management. 

 These small thermistors are ideal for a variety of applications, from human body temperature measurement to thermal profiling of electronics. 

 For over 30 years, defense subcontractors have relied on QTI's components for their most critical applications. 

DirecTemp USB Thermometers & Services


QTI’s DirecTemp™ USB thermometers give you the information you need however you need it.

The DirecTemp USB thermometer puts you in control of the temperature data you need.  Customize this data logger to your requirements by selecting from two interface options and multiple probe styles and cable configurations.  Choose from a range of tolerances up to +/- 0.05°C (from 0°C to 70°C).  Connect your DirecTemp using a plug and play or serial USB connection, and stream temperature data with easy to use software.  Configure the software with custom alerts or export the data as an Excel file.

 For over 30 years QTI Sensing Solutions has created custom sensors to meet our customers' temperature sensing needs.  Our Engineering team works with each of our customers to understand their temperature sensing application and create parts to meet their specific needs.  We design and manufacture our temperature sensors ourselves, so our customers can be assured that they are receiving the most stable, accurate and reliable sensors available. 

Not only can QTI provide thermistors and other sensing elements, but we can also provide housings, connectors, handles or strain reliefs, cable assemblies, and a variety of other value-added probe and packaging options.


or over 20 years, Defense sub-contractors have relied upon QTI thermistor components in their most critical applications. QTI's high reliability thermistors are built to meet or exceed the MIL-PRF-23648 military specification and NASA Goddard Space Flight Center (GSFC) S-311-P-827. We continue to maintain one of the largest QPL (Qualified Product Listing) product offerings of any temperature sensor supplier.

QTI maintains an extensive test laboratory, designed with defense and aerospace customers in mind. This test lab is ISO 9001:2008 and AS9100 Revision B certified. We are qualified to perform all tests dictated by the Department of Defense, Defense Logistics Agency MIL-PRF-23648, and MIL-PRF-32192 specifications. In addition we have the facilities to perform many of the tests specified in MIL-STD-202, MIL-STD-883, NASA Goddard S-311-P-18 and S-311-P-827, EEE-INST-002, TOR-2006, ESA 4006, and MIL-PRF-38534 Class K and H Element Evaluation tests.