Patent
Method and apparatus of a crystal oscillator with a noiseless and amplitude based start up control loop
TLDR
In this paper, a control circuit determines based on the measured amplitude to disable a low resistance path in the controlled switch array to reduce the applied gain below the power dissipation specification of the crystal.Abstract:
A large gain is used to start up the oscillation of the crystal quickly. Once the oscillation starts, the amplitude is detected. A control circuit determines based on the measured amplitude to disable a low resistance path in the controlled switch array to reduce the applied gain below the power dissipation specification of the crystal. Another technique introduces a mixed-signal controlled power supply multi-path resistive array which tailors the maximum current to the crystal. A successive approximation register converts the amplitude into several partitions and enables/disables one of several power routing paths to the inverter of the oscillator. This allows a better match between the crystal selected by the customer and the on-chip drive circuitry to power up the oscillator without stressing the crystal. The “l/f” noise of the oscillator circuit is minimized by operating transistors in the triode region instead of the linear region.read more
Citations
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Patent
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Jun Zhang,Xiuqiang Xu +1 more
TL;DR: In this article, an oscillator circuit generates a voltage signal and the magnitude of the voltage signal is measured and compared with predetermined upper and lower voltage signals by an internal test circuit.
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Oscillator circuit with reconfigurable oscillator amplifier and/or hybrid amplitude calibration circuit and associated method
TL;DR: In this article, a reconfigurable oscillator amplifier (110, 400) is used to be coupled to a resonant circuit (102, R2) in parallel, which supports different circuit configurations for different operation modes, respectively.
References
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Patent
Crystal oscillator with peak detector amplitude control
TL;DR: In this paper, a crystal oscillator with a wide dynamic frequency range is described, which is capable of supporting a broad range of crystal types, such as the clipping of signals, the introduction of signal distortion and unwanted signal harmonics.
Patent
Regulated, symmetrical crystal oscillator circuit and method
TL;DR: In this paper, a crystal oscillator circuit is provided, where voltage placed across the crystal is regulated, and gain from the amplifier is also regulated so that unwanted nonlinearities and harmonic distortion is not induced within the crystal to cause frequency distortion and unwanted modes of oscillation.
Patent
Oscillation drive device, physical quantity measurement device and electronic apparatus
Naoki Yoshida,Masahiro Kanai +1 more
TL;DR: In this article, an oscillation drive device with a vibrator for exciting a driving vibration on the vibrator was presented. But the oscillation detector was not used to detect oscillations in the oscillator's oscillation loop.
Patent
Low noise reference oscillator with fast start-up
TL;DR: In this article, a hybrid automatic gain control (AGC) loop that switches between an analog AGC loop at oscillator start up and a digital AGC at steady state operation is presented.
Patent
Oscillator circuit with an inventor amplifier having reduced consumption
TL;DR: In this paper, an inverter oscillator circuit delivering an alternating output signal (Sosc) and including a parallel arrangement, between an input terminal (A) and an output terminal (B), of inverter amplifier means (2, 3), a resonator (1) and a resistor (4), first and second load capacitors (5, 6) being respectively connected between said input and output terminals (A, B), and a supply potential (Vss, VDD, VR), on the one hand, and a means (9, 90) for smoothing an amplitude