Abstract: A layer of dopant is implanted in the passivation of a semiconductor die to facilitate testing of the die by a scanning electron microscope voltage contrast system. The layer of dopant is capacitively coupled to circuits under the passivation and is coupled to ground to allow charge to bleed to ground through a high resistivity path. The resistivity is low enough to allow E-beam charge bleed off, but not bleed off of higher frequency capacitive coupled signals. The disclosure is also applicable to photo generated electron voltage contrast.

Abstract: A communication receiver (12) is provided having a radio frequency section (20) for receiving a communication signal (14) and a corresponding code signal (16) carrying an identification code. An intermediate frequency section (26) is coupled to radio frequency section (20) to convert the frequency of said communication signal. A decoder (42) having a memory for storing a security code, is coupled to radio frequency section (20) and intermediate frequency section (26). Decoder (20) is operable to compare the identification code and the security code and selectively disable the intermediate frequency section in response.

Abstract: A passive magnetic bearing assembly for a rotating shaft including:a. a journal subassembly suitable for mounting to the shaft so as to rotate with the shaft, the journal subassembly comprising a housing forming a chamber containing a journal magnetic material, a flexible fluid-filled hollow member which compensates for changes in the unoccupied volume within the chamber due to thermal expansion and changes in internal pressure, and a damping fluid in the chamber; andb. a bearing subassembly annularly and concentrically disposed around the journal subassembly such that a clearance is formed between the bearing and journal subassemblies, the bearing subassembly comprising a housing forming a chamber containing a bearing magnetic material, a flexible hollow fluid-filled member which compensates for changes in the unoccupied volume within the chamber due to thermal expansion and changes in internal pressure, and a damping fluid in the chamber.