MDSM-4R-32-38 - MDSM-4 Series

Series: MDSM-4
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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.

A sub-miniature, surface mount, normally open switch with a 15.24mm long x 2.28mm diameter (0.600" x 0.090") glass envelope. Capable of switching 200Vdc at 10W. Available sensitivity range of 12-38 AT. High insulation resistance of 1010 ohms minimum and contact resistance of less than 100 milliohms. Available in axial-leaded version (MDCG-4). Ideally suited for reed relays, security, metering, limit sensing, telecom and office equipment applications. Available in bulk packaging or tape and reel.


  • Surface mount, normally open switch capable of switching 200Vdc or 0.5A at up to 10 Watts
  • Available sensitivity range of 12-38 AT


  • Hermetically sealed switch contacts are not affected by and have no effect on their external environment
  • Zero operating power required for contact closure
  • Excellent for switching micro-controller logic level loads


  • Position sensing
  • Level sensing
  • Security
  • Industrial controls
  • Telecom
  • Office equipment
  • Home appliances

UL_IZLT2_E70164icon UR_NQMJ2_E471070

UL_JDYX8icon CUR_NQMJ8_E471070

UL_JDYX8icon UR_NWFW2_E471070

UL_JDYX8icon CUR_NWFW8_E471070


curus cUR_NRNT8_E47258_100213434

UR UR_NRNT2_E47258_100213434

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