B61089QDR Series - Dual port negative voltage tracking SLIC protector SOP-8

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The B61089QDR is a dual channel SLIC ( Subscriber Line Interface circuit ) battery tracking protector. It consists of two pairs of identical protection thyristors integrated with two anti-series diodes to protect the SLIC against lightning induced surges and power fault events. It is designed specifically for dense component PC boards in modern telecom and datacom applications where space is concern. The gated thyristor protectors which have crowbarring function, provide tracking battery protection down to -170V. The anti-series diode provides protection of positive surge events by diverting the surge energy to the ground. The B61089QDR has a robust surge current capability which help the telecom and datacom products to comply with different surge standards such as Telcordia GR-1089, ITU-T K.20, K.21 and YD/ T950. For compliance with Enhanced Levels test conditions of ITU-T, TIA968-B, or GR-1089, additional series resistance in the Tip / Ring pairs may be required. The SLIC chipset voltage reference may change as the on-hook/ off-hook line condition changes. Therefore, this component is referenced to the - VBAT so that its negative protection threshold follows this changing reference voltage level. This B61089QDR utilizes a transistor gain network so that a low 5 mA current level will activate the thyristor based portion of this protector component during negative events. This also allows an easier turn on during slow rising power fault events. For all positive disturbances, the fast switching diode connected to earth reference will provide the needed protection. 


  • Dual port negative voltage tracking programmable component
  • Supports battery voltages down to -170V
  • Low gate triggering current 5 mA max
  • Fails in a short circuit condition when it is surged in excess of its ratings to protect all downstream equipment
  • Surge capability does not degrade after multiple surge events within its ratings
  • High holding current -150mA min
  • Specified 2/10 limiting voltage
  • Integrated diodes for positive surge protection
  • MSL: Level 1 - unlimited
  • 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
Pins T-RIDRM @
IH (mA)Regulatory RequirementsIpp5x310Ipp2x10Ipp8x20Pins T-GPartner ECAD ModelsStockSamples
B61089QDR1706-1/6-85150GR1089 INTRA-BUILDING
GR1089 I
Part # Part Description RoHS Pb-free RoHS (2015/ 863/EU) Certificate REACH (SVHC’s) Declaration Halogen Free REACH (SVHC’s)
B61089QDR Dual voltage negative SLIC protector RoHS No 06/28/2016 PbFree No 06/28/2016 CoC_RoHS10_B61089QDR_03-22-2021 REACH211_Declaration_B61089QDR_03-22-2021 Yes
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