Patent
Method and apparatus for providing a modulation current
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TLDR
In this article, the authors proposed a modulation current that includes output impedance compensation with a feed-forward bandwidth enhancement and pre-distortion modulation to control waveform transition symmetry, where the output impedance is compensated by a feedback circuit that senses output node voltage and increases the overdrive voltage of a current source.Abstract:
Techniques are disclosed for providing modulation current that includes output impedance compensation with a feed-forward bandwidth enhancement and pre-distortion modulation to control waveform transition symmetry A feedback circuit senses output node voltage and increases the overdrive voltage of a current source This offsets the loss of current due to channel length modulation and increases the effective output impedance of the source A feed-forward circuit enhances the bandwidth of the impedance compensation feedback loop Waveform transition symmetry is improved by pre-distorting a laser modulation current by introducing an undershoot current on the falling edge of the modulating currentread more
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References
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Patent
Calibration of laser systems
TL;DR: In this paper, a method for determining a condition of the laser system includes determining a change in a laser current from an initial value, which is the difference between the values of a power supply current.
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High-speed CMOS driver for vertical-cavity surface-emitting lasers
TL;DR: In this paper, a high-speed driver circuit was proposed to interface with and enhance the performance of vertical-cavity surface-emitting laser (VCSEL) diodes used within fiber optic communication systems.
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Laser driver pre-emphasis and de-emphasis method and/or architecture with tuning and duty cycle control
TL;DR: In this article, a modulator circuit, a first and a second control circuit are configured to generate a modulated differential output signal in response to a differential input signal, and the first control circuit may be configured to control a first predistortion of the differential inputs and the second controlling a second portion of the outputs.