A DC-coupled laser driver circuit with large modulation current belongs to the optical field. The present invention solves the problem that the conventional laser driver circuit consumes too much voltage margin because the transistor is used as the tail current source, resulting in a small modulation current. The present invention includes a negative feedback unit, an adaptive drive unit, a mirrored tail current source, a resistor R11, a resistor R12, a bias current source IBIAS and a diode D2; The resistor R12, laser D1, resistor R11, and bias current source IBIAS are connected in series between the voltage VCC and the ground in sequence; the input terminal of the negative feedback unit is connected to the data signal input ports TINP and TINN, the output terminal of the negative feedback unit is connected to the input terminal of the adaptive drive unit, the output terminal of the adaptive drive unit is connected to the control signal input terminal of the mirrored tail current source, a drive signal output terminal of the mirrored tail current source is connected to the anode of the laser D1 through a diode D2, the other drive signal output terminal of the mirrored tail current source is connected to the cathode of the laser D1.

Described are methods and a system for atomic memory operations with contended cache lines. A processing system includes at least two cores, each core having a local cache, and a lower level cache in communication with each local cache. One local cache configured to request a cache line to execute an atomic memory operation (AMO) instruction, receive the cache line via the lower level cache, receive a probe downgrade due to other local cache requesting the cache line prior to execution of the AMO, and send the AMO instruction to the lower level cache for remote execution in response to the probe downgrade.

An optoelectronic device includes a laser diode having a cathode terminal and an anode terminal, which is connected to a driving voltage. A driver is coupled to drive current pulses through the laser diode from the anode terminal to the cathode terminal. A discharge switch has a first switch terminal connected to the cathode terminal and a second switch terminal connected to a discharge voltage, which is equal to or greater than the driving voltage, and is configured, when closed, to raise the cathode terminal to the discharge voltage. A switch control circuit has an input connected to the cathode terminal and an output connected to close the discharge switch in response to the current pulses occurring at the input.

A first conductive pattern (13) is provided on an upper surface of the submount (7). A GND pattern (9) is provided on a lower surface of the submount (7). A lower surface electrode (21) of a capacitor (3) is bonded to the first conductive pattern (13) with solder (22). An upper surface electrode (23) of the capacitor (3) is connected to a light emitting device (2). A terminating resistor (4) is connected to the first conductive pattern (13). The first conductive pattern (13) has a protruding portion (25) which protrudes outside from the capacitor (3) in planar view. A width of the protruding portion (25) is narrower than a width of the capacitor (3).

To reduce crosstalk between bond wires, one illustrative integrated circuit includes an array of photoemitters arranged along a centerline, with adjacent photoemitters having contact pads on opposite sides of the centerline. An illustrative assembly includes an integrated circuit chip having an array of photoemitter contact pads; a printed circuit board having a recess in which the integrated circuit chip is mounted; and bond wires connecting the contact pads with respective contact pads on the printed circuit board. An illustrative cable connector includes a module that optically couples optical fibers to an array of photoemitters on an integrated circuit chip mounted to a printed circuit board. Each photoemitter has contact pads connected to the printed circuit board contact pads by bond wires, the bond wires for each photoemitter being routed in an opposite direction relative to the bond wires for any adjacent photoemitters in the array.

An optoelectronic device includes a substrate and at least three emitters, which are disposed on the substrate and are configured to emit respective beams of light. A plurality of waveguides are disposed on the substrate and have respective input ends coupled to receive the beams of light from respective ones of the emitters, and curve adiabatically from the input ends to respective output ends of the waveguides, which are arranged on the substrate in an array having a predefined pitch. Control circuitry is configured to apply a temporal modulation independently to each of the beams of light.

A drive circuit for a direct modulated laser and a direct modulated optical transmitter. The drive circuit includes a service data drive unit, a voltage configuration unit, a monitoring data modulation unit, and a monitoring current generation unit. Output terminals of the voltage configuration unit and the monitoring data modulation unit are connected to a same input terminal of the monitoring current generation unit. An output terminal of the service data drive unit is connected to a current sink interface of the monitoring current generation unit, and is suitable for connecting a direct modulated laser. In the technical solution, a low-speed monitoring data signal is mixed into an average optical power signal of a high-speed service data light wave from the direct modulated laser, then is extracted from the received optical signal by a remote optical receiver, enabling the drive circuit to be remotely monitored.

A method (900) includes a gain current (I.sub.GAIN) to an anode of a gain-section diode (D.sub.0) disposed on a shared substrate of a tunable laser (310), delivering a modulation signal to an anode of an Electro-absorption section diode (D.sub.2) disposed on the shared substrate of the tunable laser, and receiving a burst mode signal (330) indicative of a burst-on state or a burst-off state. When the burst mode signal is indicative of the burst-off state, the method includes sinking a sink current (I.sub.SINK) away from the gain current at the anode of the gain-section diode. When the burst mode signal transitions to be indicative of the burst-on state from the burst-off state, the method includes ceasing the sinking of the sink current away from the gain current and delivering an overshoot current (I.sub.OVER) to the anode of the gain-section diode.

A method for physical random number generation includes the steps of: modulating the gain of a vertical-cavity surface-emitting laser periodically from the lower threshold to the upper threshold and back; maintaining the gain per round trip positive for a longer period than the round trip time of the cavity; maintaining the net gain per round trip negative for a longer period than the round trip time of the cavity, in order to create optical pulses of random amplitude; detecting the optical pulses; converting the optical pulses into electrical analog pulses; and digitising the electrical analog pulses into random numbers.

A circuit is disclosed having a component having repeatable distortion characteristics; and a drive circuit for providing a drive signal and comprising a non-linear filter for pre-compensating for distortion introduced by the component having repeatable distortion characteristics in response to the drive signal, the distortion having a non-linear response to the drive signal.