A low-noise, 2.5V reference is constructed by stacking four 2.5V reference ICs in series. The resulting 10V output is divided back to 2.5V, and a low-noise unity-gain buffer added. This stacked-reference design reduces noise because the noise from each IC, being random and uncorrelated, partially cancels each other out. The low-frequency 1/f noise (LF noise) generated by a voltage reference at ...

In this paper, an improved algorithm for active control of fan noise is proposed. The main idea behind this work is to optimize the components in the reference signal using the information from the unwanted fan noise. In the algorithm, the linear prediction coefficients obtained from the noise is used to build an autoregressive model. Then the model is applied to the reference signal to improve...

The noise power of bandgap references is directly related to the current consumption of the bandgap reference. This paper describes the design of low-noise bandgap references. It is shown that for an idealized bandgap reference, a fundamental noise limit exists when the limited current consumption is a constraint. A design example is given of a 1 V bipolar bandgap reference with a current consu...

Several adaptive order statistic filters (OSF) are developed and compared for channel characterization and noise suppression in images and 3-D CT data. Emphasis has been put on the situation when a noise-free reference image is not available but instead we can have a sequence of two noisy versions of the same image (or a 3-D data slice). One of the noisy images is used as the reference in the O...

Phase locked loops in 10 Gb/s and faster data links are low phase noise devices. Characterization of their phase jitter transfer functions is difficult because the intrinsic noise of the PLLs is comparable to the phase noise of the reference clock signal. The problem is solved by using a linear model to account for the intrinsic noise. This study also introduces a novel technique for measuring ...