Patent ID: 7154727
Filing Date: 2006-12-26
Classification: H02H,H04M

Abstract:
1. A circuit to protect a protected device from a surge voltage, the circuit being connected between said device and first and second nodes to which the surge voltage may be applied, wherein a charge storage device is connected between third and fourth nodes and the protected device is operatively connected to the third node and a fifth node, the circuit comprising: a first overvoltage protection device coupled between the fourth node and the fifth node, the fourth and fifth nodes being operatively connected to the first and second nodes, respectively, a clamping voltage of the first overvoltage protection device being less than a switching voltage of the first overvoltage protection device; and a second overvoltage protection device coupled between the third node and the fifth node; wherein a voltage between the third and fifth nodes during the surge voltage is substantially less than a switching voltage of the second overvoltage protection device for at least a portion of the duration of the surge voltage, wherein the second overvoltage protection device comprises a SIDACtor® device, and wherein the first overvoltage protection device comprises a SIDACtor® device.