Applied Micro Circuits Corporation

Other

Cosemi Technologies, Inc.

John J Stronczer

Todd M Tanji

Keith R Maile

Prashant K Singh

Scott Redinger

Helga Foulk

Robert John Schuelke

Iain Ross Mactaggart

Robert Monroe Smith

Charles Phillip McClay

Wu-Chun Chou

A power efficient device for driving a load comprising a low current path and a high current path, wherein the high current path is driven by a first voltage source. In order to accommodate larger turn on voltages of possible load devices while maintaining low power operation, an additional voltage source exceeding the voltage source in the high current path is introduced in the low current path.

Pass device with boost voltage regulation and current gain for VCSEL driving applications

A laser driver includes two DC-coupled differential drive circuits in which the common mode voltage of the first differential drive circuit is maintained a level affording a high compliance voltage for a laser diode driven by the second differential drive circuit. This is accomplished by means of an operational amplifier which compares the common mode voltage of the second differential drive circuit to a reference voltage. The operational amplifier operates in a closed-loop configuration to draw current through a common mode bias resistor in the first differential drive circuit in order to force the common mode voltage of the second differential drive circuit to a desired value determined by the reference voltage.

High compliance laser driver

Drive circuitry to provide a DC bias voltage and a high frequency modulation current to an electroabsorption modulator (EAM), including a high frequency modulation current source, a coupling capacitor, and a first DC lead. The drive circuitry may include termination circuitry. One lead of the high frequency modulation current source is electrically coupled to the first semiconductor type contact of the EAM and the other lead of the high frequency modulation current source is electrically coupled to an AC ground. The coupling capacitor includes a first electrode electrically coupled to the second semiconductor type contact of the EAM, a second electrode electrically coupled to the AC ground, and a dielectric layer between the electrodes. The first DC lead is electrically coupled to the EAM-side capacitor electrode and configured to be coupled to a first DC potential.

Device for coupling drive circuitry to electroabsorption modulator

An optical transceiver system includes circuitry including a light-emitting device, a driver for the light-emitting device being coupled to the light-emitting device for providing activating power to said light-emitting device and an optical detector disposed to receive light emitted from the light-emitting device, said circuitry being substantially constructed using CMOS technology. A calibration interface is coupled to the circuitry for automatically executing an iterative cycle for a calibration of optical link parameters. And, an optical loop-back is included for optically coupling the light-emitting device and the optical detector, the optical detector receiving light emitted by the light-emitting device, the light emission being selectively stimulated by the calibration interface, the received light emission being communicated to the calibration interface for comparison with a known light signal. A method of automatic calibration and control of optical link parameters in a VCSEL-based optical transceiver is included.

Methods and systems for control and calibration of VCSEL-based optical transceivers

High-speed driver circuits interface with and enhance the performance of vertical-cavity surface-emitting laser (VCSEL) diodes used within fiber optic communication systems, according to embodiments of the invention. A reference diode is formed from a first transistor, and a first current mirror sets a modulation current through the reference diode for driving a light-emitting device. A second current mirror sets a reference biasing current to maintain a constant bias of the reference diode. A first capacitor, charged by a differential amplifier and coupled to the reference diode, supplies complementary charge to the reference diode during differential input voltage transitions. Components of the driver circuit provide asymmetrical operation of the laser, allowing rapid light-emitting-device turn-on and turn-off.

High-speed CMOS driver for vertical-cavity surface-emitting lasers

A transimpedance amplifier according to the present invention is designed for high-speed fiber optic communications. The transimpedance amplifier preferably includes an input stage, a second stage and a bias generator. The input stage is operably coupled to the second stage and has an input impedance. The second stage has an output impedance. The bias generator is operably coupled to the input stage and the second stage, and operates to bias the input stage and second stage such that the input impedance substantially matches the output impedance. In this manner, the input and output impedances of a transimpedance amplifier of a fiber optics communication receiver are controllable to a desired impedance for interfacing with a transmission line.

Growing community of inventors

Mattawan, MI, United States of America

John J Stronczer