Parallel optical transceiver module having a balanced laser driver arrangement

A parallel optical transceiver module for simultaneously transmitting multiple optical signals over multiple respective optical transmit channels, the optical transceiver module comprising:

• a circuit board comprising a substrate having an upper surface and a lower surface, the upper and lower surfaces of the substrate having electrical conductors disposed thereon, wherein at least some of the electrical conductors disposed on the upper surface of the substrate are electrically connected with at least some of the electrical conductors disposed on the lower surface of the substrate;
• a laser diode integrated circuit (IC) chip mounted on the upper surface of the circuit board, the laser diode IC chip having at least a first side and a second side that are substantially parallel to one another, the laser diode IC chip comprising N laser diodes configured to generate N respective optical signals in a direction away from the upper surface of the circuit board, wherein N is an integer that is equal to or greater than 2;
• a first laser diode driver IC chip mounted on the upper surface of the circuit board in electrical communication with the laser diode IC chip, the first laser diode IC chip having at least a first side and a second side that are substantially parallel to one another, the first side of the first laser diode IC chip being proximate to the first side of the laser diode IC chip, the first laser driver IC chip having driver circuitry configured to drive L of the N laser diodes, wherein L is an integer that is less than N and greater than or equal to 1;
• a second laser diode driver IC chip mounted on the upper surface of the circuit board in electrical communication with the laser diode IC chip, the second laser diode IC chip having at least a first side and a second side that are substantially parallel to one another, the first side of the second laser diode IC chip being proximate to the second side of the laser diode IC chip, the second laser driver IC chip having driver circuitry configured to drive M of the N laser diodes, wherein M is an integer that is less than N and greater than or equal to 1,
• a first set of monitor photodiodes integrated in the first laser diode driver IC chip, the first set of monitor photodiodes comprising at least one monitor photodiode, said at least one monitor photodiode of the first set of monitor photodiodes being positioned in close proximity to the first side of the first laser diode driver IC chip;
• and
• a second set of monitor photodiodes integrated in the second laser diode driver IC chip, the second set of monitor photodiodes comprising at least one monitor photodiode, said at least one monitor photodiode of the second set of monitor photodiodes being positioned in close proximity to the first side of the second laser diode driver IC chip.

A method for simultaneously transmitting multiple optical signals over multiple respective optical transmit channels in a parallel optical transceiver module, the method comprising:

• causing a first set of electrical laser diode driver signals to be sent over a first set of conductors of a first laser diode driver IC chip mounted on an upper surface of a substrate to a laser diode IC chip mounted on the upper surface of the substrate, the laser diode IC chip comprising N laser diodes configured to generate a N respective optical signals travelling in a direction away from the upper surface of the substrate, wherein N is an integer that is equal to or greater than 2, the first laser diode driver IC chip having driver circuitry configured to drive L of the N laser diodes, wherein L is an integer that is less than N and greater than or equal to 1;
• and
• causing a second set of electrical laser diode driver signals to be sent over a second set of conductors of a second laser diode driver IC chip mounted on the upper surface of the substrate to the laser diode IC chip, wherein the second laser diode driver IC chip has driver circuitry configured to drive M of the N laser diodes, wherein M is an integer that is less than N and greater than or equal to 1, wherein the first and second sets of electrical laser diode driver signals sent over the first and second sets of conductive pathways from the first and second laser diode driver IC chips to the laser diode IC chip cause the N laser diodes of the laser diode IC chip to generate the N optical signals;
• wherein the laser diode IC chip is located in between the first and second laser diode driver IC chips such that:
• a first side of the first laser diode driver IC chip is proximate to a first side of the laser diode IC chip;
• and a first side of the second laser diode driver IC chip is proximate to a second side of the laser diode IC chip,
• wherein the first laser diode driver IC chip has a first set of monitor photodiodes integrated therein, the first set of monitor photodiodes comprising at least one monitor photodiode, said at least one monitor photodiode of the first set of monitor photodiodes being positioned in close proximity to the first side of the first laser diode driver IC chip, and wherein the second laser diode driver IC chip has a second set of monitor photodiodes integrated therein, the second set of monitor photodiodes comprising at least one monitor photodiode, said at least one monitor photodiode of the second set of monitor photodiodes being positioned in close proximity to the first side of the second laser diode driver IC chip.