B9110DF Series - Single port, polarity tracking SLIC protector, programmable tracking protection

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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.

This single port polarity programmable B9110DF protector is specifically designed to protect smart ringing SLICs with dual power supplies. This B9110DF will protect the SLIC interface against lightning induced surges and power fault events. It contains fast switching crowbarring structures that are compatible with the Basic levels outlined in ITU K.20, K.21. For compliance with the Enhanced levels, an additional resistor in series with tip and ring may be required. This programmable protector may also be beneficial for YD/T 950, TIA-968-B, GR-1089-Core Issue 6and UL/EN/IEC 60950-1 compliance.

The SLIC chipset voltage reference may change as the on-hook/off-hook line condition changes. Therefore, this protector is referenced to the +VBAT and -VBAT references so that its protection thresholds follow these reference voltage changes by approximately 1.4V. The B9110DF gates utilize transistor gain networks so that a low 5 mA current level will activate these four separate protection structures.

This allows for easier turn on during slow rising ac power fault events.


  • High performance protection for SLICs with + VBAT and –VBAT references and with changing VBAT references
  • Wide -110V to +110V programming range
  • Low gate current triggering
  • ESD Immunity(HBM):JESD22 Class 3B, ≥8KV
  • MSL: Level 1 – unlimited
  • Tracking crowbarring component
  • Fails short circuit when surged in excess of its ratings to protect SLIC Chipset
  • Surge capability does not degrade after multiple surge events within its ratings
  • RoHS compliant and lead-free


  • Wireless In the Local Loop (WLL)
  • Voice applications which require regenerated POTS
  • VoIP applications
  • PBX
  • FXS applications
  • Digital Pair Gain systems (DPG) and Digital Loop Carrier systems (DLC)
  • Small Office Home Office (SOHO) 

Access specifications, certifications, check availability and order parts below

Catalog #VDRM T-R
SizePins T-RCO 2V
IH (mA)Ipp10x1000Ipp2x10Ipp5x310Pins T-GStock

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