Cryocon Navigation Bar Products Support Company Home Distributors Home

Home > Temperature Sensors > Product Folder

S950 Silicon Diode Temperature Sensor

Product Folder

  • S950-Family
  • S950-BB
  • S950-SM
  • S950-CP

S950 Sensor Packages

S950 temperature sensor family

Silicon diodes are easily the most common temperature sensors used in cryogenic applications. They offer good sensitivity and a wide range of operation compared to other devices. Further, they have excellent interchangeability and stability.


The S950 is offered in three packages to fit a wide range of applications:

  • The BB package is an industry standard 0.310” bobbin with 36” leads. It is one of the easiest to use cryogenic sensors available.
  • The SM package includes an insulating substrate and is designed for direct surface mounting. Features include extremely small size and 3” copper leads that greatly simplify thermal anchoring.
  • The CP package is the smallest cryogenic temperature sensor available. Bonded lead wires extend high temperature operation to 500K.

For applications above 50K, please consider Cryo-con's Platinum RTDs

S950 Bobbin Package

S950 Bobbin PackageS950 Bobbin Drawing

Temperature Range: 1.5 to 400K.

Marking: Individual serial number on the top of the package.

Mass: 1.1g excluding leads.

Construction: Bobbin Material is gold plated oxygen free hard copper. Sensor bonding is Stycast® epoxy.

Leads: 36”, 36AWG Phosphor-Bronze. Four-lead color coded cryogenic ribbon cable. Insulation is heavy Formvar® . Strain relief is Teflon®.

Mounting: 4-40 brass machine screw. A thin layer of Apiezon® N grease is recommended.

S950 SM Package

S950 SM packageS950 Package Mechanical Drawing

Temperature range: 1.5 to 400K.

Mass: 37mg

Thermal response time: <10mS at 4.2K, 100mS at 77K and 200mS at 305K.

Construction: Package material is gold plated OHFC copper on an Alumina substrate.

Leads: 3”, 37 AWG copper with Polyimide insulation. Positive connection is red and negative is black. Lead attach is 60/40 solder.

Mounting: Varnish, epoxy or clamp to a clean flat surface. Thermally anchor copper leads.

S950 Cap Package:

S950 CP package photoS950 CP package drawing

Temperature Range: 1.4 to 500K

Mass: 32mg

Thermal response time: <10mS at 4.2K, 100mS at 77K and 200mS at 305K.

Construction: Package material is Alumina with gold plated OHFC copper end caps. Leads are 3”, 37 AWG copper with Polyimide insulation.

Mounting: Sensor body must be electrically insulated from mounting surface. Attach using varnish or epoxy. Thermally anchor the copper leads.





  • Good sensitivity over the temperature range from 1.4K to 400K (500K in the CP package). High sensitivity in the range from 20K to 1.4K.
  • Conforms to the standard S950 calibration curve with high accuracy, giving excellent interchangeability.
  • Available in two tolerance grades. Accuracy can be further improved using Cryo-con's CalGen® software.
  • Available in a variety of packages.
  • High repeatability and stability. Minimum long term drift.
  • Fabricated with non-magnetic materials.



  • Wide temperature range measurements outside of a magnetic field.
  • Cryocoolers and cryogen free systems.

  • Nitrogen and Helium flow cryostats.
  • Cryogenic liquifiers, Storage tanks.
  • Systems requiring rapid thermal response.


Temperature Range: 1.5K to 400K for the BB and SM packages. 1.5K to 500K for the CP package.

Standard Curve: Cryo-con S950.

Excitation Current: 10µA ±0.1%

Repeatability:10mK @4.2K, 16mK @77K, 75mK @273K.

Magnetic Field Use: Not recommended for fields above 0.1 Tesla or temperature below 40K.

Use in Radiation: Not recommended for high
radiation environments.

Maximum Temperature: Do not store above 500K.

Maximum Reverse Voltage: 60V.

Maximum Excitation Current: 2mA.

Power Dissipation: 16µW at 4.2K.

Tolerance Bands

1.5K - 30K
30K - 100K
100K - 400K
Band A ±0.1K ±0.2K ±1.0K
Uncalibrated ±0.2K ±0.4K ±1.0K

Temperature Response

S950 temperature response



Sensitivity (mV/K)

S950 Sensitivity



Low Temperature Response

S950 Low Temperature Response



Standard Temperature Response

1.5 1.63 -31.5
4.2 1.55 -38.9
77.35 1.03 -1.7
273 0.62 -2.29
500 0.1 -2.1
CalGen™ and Cryo-Con™ are registered trademarks of Cryogenic Control Systems, Inc.
All other product and company names are trademarks or trade names of their respective companies.
Tel: (858) 756 3900   Fax: (858) 759 3515   
Specifications subject to change without notice. ©Cryogenic Control Systems, Inc. 1998 - 2021