B61089QDR

This component is designed to protect two different SLIC (Subscriber Line Interface Card) tip/ring pairs with independent voltage tracking for each pair. This B61089QDR will protect the SLIC interface against lightning induced surge and power fault events. It contains fast switching crowbarring structures for negative events and a simple fast switching diode structure for positive events. It is compatible with the Basic Levels of ITU K.20 and K.21. For compliance with the Enhanced Levels of ITU, TIA 968-B, or GR-1089, an additional series resistor in the tip and ring leads 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 B610989QDR 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.