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How does the oscillator circuit work?
An oscillator is a circuit which produces a continuous, repeated, alternating waveform without any input. Oscillators basically convert unidirectional current flow from a DC source into an alternating waveform which is of the desired frequency, as decided by its circuit components.
What is oscillator BJT?
BJT as oscillator – definition Oscillations are observed in a BJT oscillator circuit on connecting the feedback network. The cause of resonance is that the feedback network is slower and the rise/fall of current/voltage in the feedback network occurs at a specific rate depending on the elements used in the feedback.
How does a BJT work in a bipolar junction transistor?
A BJT uses a small current at its base to control a much larger collector current. Before we go any further, it may be useful to define some important terms concerning the operation of a bipolar junction transistor.
What is the approximate oscillation frequency of a BJT circuit?
Notice with the marker that the approximate oscillation frequency with this circuit is 1.32 GHz. Now that the linear analysis shows that this circuit should oscillate at 1.32 GHz, non-linear oscillator characteristics can be simulated. The OSCTEST element is removed and the OSCAPROBE is hooked into the feedback loop.
How does the BJT work in saturation mode?
Saturation refers to a region of operation where maximum collector current flows and the BJT acts like a closed switch from collector to emitter. In this mode the BC junction forward biases and maximum current flows. The collector current cannot increase any more, even with an increase in base current.
How does a BJT work on a silicon wafer?
Instead, semiconductor manufacturers use a diffusion process which melts the base into the collector region and then melts the emitter region into the base region (for an NPN BJT). Thousands of transistors are diffused on a silicon wafer from which induvial transistors are then cut before being sealed in plastic or metal.