Abstract: A fastener for securing a printed circuit board to a chassis includes a body portion, legs depending from the body portion, the legs being adapted for removable attachment within holes in the chassis, a hook for slidably engaging a slot on a printed circuit board inserted thereon, and a grounding element for providing an electrical connection between the printed circuit board and a shield on the chassis. The fastener described herein enables one chassis design to accommodate a variety of sizes of printed circuit boards merely by forming holes at particular points on the chassis, thereby avoiding the expense of redesigning a chassis to accommodate a new printed circuit board.

Abstract: A sensor circuit for monitoring the operation of a fan in an electronic device includes a current sensor that produces a voltage signal proportional to the magnitude of the current flowing through the fan. The proportional voltage signal is filtered to extract an rms dc signal that then is compared with a minimum and maximum voltage threshold in two voltage comparators. If the voltage of the filtered signal exceeds the maximum threshold value, or is less than the minimum threshold value, a fan failure signal is generated and transmitted to an external monitoring unit. The sensor circuit can be implemented with a standard two-wire fan and interface connector.