Abstract: A frequency multiplier includes a capacitor circuit having a plurality of capacitors therein, and is responsive to a differential input signal applied to an inverting input node and a non-inverting input node thereof. A frequency multiplication circuit (FMC) is provided, which has a plurality of transistors therein. The FMC is configured to receive components of the differential input signal passing through the plurality of capacitors, and multiply a frequency of the components of the differential input signal. A plurality of inductor loads are provided, which are connected to an inverting output node and a non-inverting output node of the FMC, and are configured to convert a current signal generated by the FMC into a voltage signal.

Abstract: A system and method of operating a vehicle powertrain that employs active control to reduce NVH, particularly during idle. The method includes selectively operating the powertrain in at least a non-idle condition and an idle condition; receiving vibration signals from a sensor disposed on an internal combustion engine; controlling spark timing of the internal combustion engine based on vibration signals received from the sensor; and during the idle condition, modifying a speed and/or a load of the internal combustion engine based on vibration signals received from the sensor.