JM Series - DO-35 Interchangeable Glass Encapsulated Thermistors (300°C) ± 1.0°C Accuracy

Series: JM
Littelfuse Leaded Thermistors DO-35 Interchangeable - JM image
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

Littelfuse low cost interchangeable glass encapsulated thermistors are manufactured using super stable, precision NTC chips which are hermetically sealed in a glass (DO-35 diode style) package. The result is a device which exhibits excellent long term reliability and stability even when subjected to severe environmental or thermal conditions. They are well suited for uses where their interchangeability eliminates the necessity for costly individual circuit calibration. Their uniform dimensions and axial lead configuration make them especially suitable for use with automatic insertion equipment.


  • High temperature capability to +300°C
  • Hermetically sealed glass package
  • High accuracy
  • Low cost
  • Excellent long-term stability
  • High voltage insulation
  • Tinned CCS lead wires are solderable or weldable


  • Special lead forms
  • Non-standard resistance values and tolerances
  • Point matched at specified temperatures
  • Tape and reel packaging


  • Interchangeability accuracy of ±1.0°C (0°C to +100°C)
  • Thermal time constant: 5 seconds (still air)
  • Thermal time constant: 0.5 seconds (stirred liquid)
  • Dissipation constant: 2 mW/°C (still air)

Access specifications, certifications, check availability and order parts below

Catalog #Resis Ω @ 25°CR-T CurveOperating TemperatureEngineering DrawingRT TableStockSamplesCompare
103JM1A10000J-55° to 300°CEngineeringRTCheckOrder
104JM1A100000J-55° to 300°CEngineeringRTCheckOrder
104JM2B100000J-55° to 300°CEngineeringRTCheck
203JM1A20000J-55° to 300°CEngineeringRTCheck
253JM1A25000J-55° to 300°CEngineeringRTCheck
503JM1A50000J-55° to 300°CEngineeringRTCheck
Part # Part Description RoHS Pb-free RoHS (2015/ 863/EU) Certificate REACH (SVHC’s) Declaration Halogen Free REACH (SVHC’s) IPC-Material Declaration
103JM1A THERMISTOR, US SENSOR RoHS No 07/26/2020 PbFree No 07/26/2020 CoC_RoHS9_103JM1A REACH209_Declaration_103JM1A Yes
Does not Contain
503JM1A NTC THERMISTOR 50K OHM 1C DO35 RoHS No 02/13/2019 PbFree No
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