Symmetrical, direct coupled laser drivers

摘要

Symmetrical, direct coupled laser drivers for high frequency applications. The laser drivers are in integrated circuit form and use a minimum of relatively small (low valued) external components for driving a laser diode coupled to the laser driver through transmission lines. An optional amplifier may be used to fix the voltage at an internal node at data frequency spectrum to improve circuit performance. Feedback to a bias input may also be used to fix the voltage at the internal node. Programmability and a burst mode capability may be included.

主权项

1. A laser diode driver comprising:
a power supply connection, a laser diode anode connection, a laser diode cathode connection, a first bias connection and a circuit ground connection; a first inductor coupled between the power supply connection and the laser diode anode connection; a second inductor coupled between the laser diode cathode connection and the first bias connection; and a first capacitor coupled between the first bias connection and the circuit ground connection; a first resistor coupled between the power supply connection and the laser diode anode connection; a second resistor coupled between the laser diode cathode connection and the first bias connection; a current source coupled between the first bias connection and the circuit ground connection; first and second transistors, each having first, second and third terminals wherein the voltage between the first and second terminals controls the conduction between the third and first terminals, the first and second transistors having their first terminals coupled together and to the circuit ground connection, the third terminal of the first transistor being coupled to the laser diode anode connection, the second terminals of the first and second transistors being coupled to a first differential voltage source responsive to differential data inputs to controllably turn on either of the first and second transistors as a current source of a first differential current source and to turn off the other of the first and second transistors as defined by the differential data inputs; the extent to which the differential data inputs turn on either of the first and second transistors as a current source of the first differential current source and to turn off the other of the first and second transistors as defined by the differential data inputs is programmable; the second transistor having its third terminal coupled to the laser diode cathode connection.