A circuit for protecting an electronic device including a differential nulling avalanche clamp circuit (200, 300) and method of using the circuit in an electronic system (100) to limit radio frequency overdrive. The electronic system (100) includes a surge clamp (130) coupled to dissipate an electrical surge effect of a first frequency from a noise sensitive node (140) and a ring wave clamp (120) coupled to dissipate an electrical surge effect of a second frequency from the noise sensitive node (140). The ring wave clamp circuit (200, 300) includes a first bipolar junction transistor (210, 310), a second bipolar junction transistor (220, 320) coupled to the first bipolar junction transistor (210, 310), and a resistive circuit (230, 330, 340) coupled to the first and second bipolar junction transistors (210, 220, 310, 320). A method of using the electronic system (100) in a device to limit radio frequency overdrive includes the steps of driving an output node with the radio frequency signal subject to overdrive effects (410), clamping a first order overdrive effect on a first node using a first clamp circuit (420), and clamping a second order overdrive effect on the first node using the differential nulling avalanche clamp circuit (430).

 
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> Apparatus and method for generating pilot beacon signal in base stations of CDMA system

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