Abstract: Circuits for protecting devices, such as gallium nitride (GaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: Circuits for protecting devices, such as gallium nitride (GaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: Circuits for protecting devices, such as gallium nitride (GaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: A circuit and method provide a headroom voltage for a laser driver driving a laser diode such that the laser diode provides signals to an optical communications device. The circuit includes a headroom control circuit receiving the headroom voltage from the laser driver, the headroom control circuit generating a controlled voltage based on the headroom voltage, and a DC-DC converter receiving the controlled voltage from the headroom control circuit generating a voltage Vout based on the controlled voltage, and applying the voltage Vout as an input to the laser diode. The headroom control circuit and the DC-DC converter are connected in a feedback loop with the laser diode to continuously provide the voltage Vout to the laser diode, and the DC-DC converter modifies the voltage Vout to compensate for burn-in characteristics or temperature drift of the laser diode over time to maintain an optimized headroom voltage for the laser driver.

Abstract: In one example, a device having integrated package interference isolation includes a ground pad, an integrated circuit device die secured to the ground pad, a substrate secured to the ground pad, at least one a high-frequency, high-power semiconductor device secured to a top mounting surface of the substrate. For electromagnetic isolation, the integrated circuit device die includes a top metal, and the substrate includes a metal via electrically coupled to a metal trace that extends on the top mounting surface of the substrate. The device package also includes a number of ground pad bonding wires that electrically couple the redistribution layer of the integrated circuit device die and the metal trace to the ground pad. The redistribution layer of the integrated circuit device die and the metal trace and via of the substrate help to shield electromagnetic radiation between components in the device package.

Abstract: In one example, a device having integrated package interference isolation includes a ground pad, an integrated circuit device die secured to the ground pad, a substrate secured to the ground pad, at least one a high-frequency, high-power semiconductor device secured to a top mounting surface of the substrate. For electromagnetic isolation, the integrated circuit device die includes a top metal, and the substrate includes a metal via electrically coupled to a metal trace that extends on the top mounting surface of the substrate. The device package also includes a number of ground pad bonding wires that electrically couple the redistribution layer of the integrated circuit device die and the metal trace to the ground pad. The redistribution layer of the integrated circuit device die and the metal trace and via of the substrate help to shield electromagnetic radiation between components in the device package.

Abstract: A distributed driver for an optic signal generator has a first amplifier cell with one or more amplifiers configured to receive and amplify an input signal to create a first amplified signal. A second amplifier cell has one or more amplifiers configured to receive and amplify the input signal to create a second amplified signal. A first conductive path and second conductive path connects to the first amplifier cell and the second amplifier cell such that the inductance associated with the first and second conductive path counteracts a capacitance associated with the first amplifier cell and the second amplifier cell. A variable capacitor may be part of the first amplifier cell and/or the second amplifier cell to selectively tune the capacitance of the distributed driver. A distributed bias circuit may be part of the first amplifier cell and/or the second amplifier cell to bias an optic signal transmitter.

Abstract: A circuit and method provide a headroom voltage for a laser driver driving a laser diode such that the laser diode provides signals to an optical communications device. The circuit includes a headroom control circuit receiving the headroom voltage from the laser driver, the headroom control circuit generating a controlled voltage based on the headroom voltage, and a DC-DC converter receiving the controlled voltage from the headroom control circuit generating a voltage Vout based on the controlled voltage, and applying the voltage Vout as an input to the laser diode. The headroom control circuit and the DC-DC converter are connected in a feedback loop with the laser diode to continuously provide the voltage Vout to the laser diode, and the DC-DC converter modifies the voltage Vout to compensate for burn-in characteristics or temperature drift of the laser diode over time to maintain an optimized headroom voltage for the laser driver.

Abstract: An optical signal module including a driver and an optical signal module. The driver includes a differential pair configured to receive and process an input signal to create a drive signal. A modulation current source provides a modulation current to the differential pair. One or more termination resistors connected to the differential pair for impedance matching. A first switch, responsive to a first control signal, maintains charge on a charge storage device. The optical signal module includes an optical signal generator arranged between a supply voltage node and a bias current node. The optical signal generator receives the drive signal and generates an optical signal representing the input signal. A second switch is between a supply voltage node the bias current node. The second switch, responsive to second control signal, selectively establishes a short between the supply voltage node the bias current node.

Abstract: Radio-frequency signals may be switched between signal lines or signal ports in RF circuits using PIN diodes and PIN-diode driving circuitry. To achieve switching, the PIN diodes are biased at voltages as high as 20 volts or more. Circuitry for biasing PIN diodes is described that uses a low-voltage power source and a single-bit control line.

Abstract: An optical signal module including a driver and an optical signal module. The driver includes a differential pair configured to receive and process an input signal to create a drive signal. A modulation current source provides a modulation current to the differential pair. One or more termination resistors connected to the differential pair for impedance matching. A first switch, responsive to a first control signal, maintains charge on a charge storage device. The optical signal module includes an optical signal generator arranged between a supply voltage node and a bias current node. The optical signal generator receives the drive signal and generates an optical signal representing the input signal. A second switch is between a supply voltage node the bias current node. The second switch, responsive to second control signal, selectively establishes a short between the supply voltage node the bias current node.

Abstract: A multi-voltage converter is described that includes multiple programmable bias voltages of positive and negative values that may be used to bias radio-frequency components such as PIN diodes and gallium-nitride devices. Programmable voltages as high as 30 volts and as low as ?20 volts are generated. Outputs may be provided to a sequencing circuit for biasing gallium-nitride transistors and amplifiers.

Abstract: Radio-frequency signals may be switched between signal lines or signal ports in RF circuits using PIN diodes and PIN-diode driving circuitry. To achieve switching, the PIN diodes are biased at voltages as high as 20 volts or more. Circuitry for biasing PIN diodes is described that uses a low-voltage power source and a single-bit control line.

Abstract: A distributed driver for an optic signal generator has a first amplifier cell with one or more amplifiers configured to receive and amplify an input signal to create a first amplified signal. A second amplifier cell has one or more amplifiers configured to receive and amplify the input signal to create a second amplified signal. A first conductive path and second conductive path connects to the first amplifier cell and the second amplifier cell such that the inductance associated with the first and second conductive path counteracts a capacitance associated with the first amplifier cell and the second amplifier cell. A variable capacitor may be part of the first amplifier cell and/or the second amplifier cell to selectively tune the capacitance of the distributed driver. A distributed bias circuit may be part of the first amplifier cell and/or the second amplifier cell to bias an optic signal transmitter.

Abstract: Circuits for protecting devices, such as gallium nitride (VcclGaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: Circuits for protecting devices, such as gallium nitride (GaN) devices, and operating methods thereof are described. The circuits monitor a magnitude of the current in a device and reduce the magnitude of the current and/or shut down the device responsive to the magnitude of the current exceeding a threshold. These circuits safeguard devices from damaging operating conditions to prolong the operating life of the protected devices.

Abstract: A power control system comprising a laser driver that receives a data signal, and responsive to a modulation control signal and a bias control signal, processes the data signal to drive a laser to generate an optic signal that represents the data signal. A monitor photodiode configured to receive the optic signal and generate a monitor photodiode signal. A modulation control path, that processes a monitor photodiode signal and a reference signal, including at least one filter and at least one mixer. The modulation control path generates a modulation control signal. A bias control path, that processes the monitor photodiode signal and the reference signal, that includes at least one filter and at least one average weighting module to generate a modulation control signal. The bias control path and the modulation control path processing reduces the effect of the error in the monitor photodiode signal.

Abstract: A reconfigurable DC-DC converter including a controller is disclosed which automatically adjusts the mode of operation (buck mode or boost mode) depending on the system requirements and is able to achieve the maximum efficiency and the lowest inductance current. The method of switching between buck and boost mode allows the converter to operate to 100% duty cycle for buck mode and 0% duty cycle for boost mode. This maximizes efficiency since the buck-boost mode of operation is eliminated and improves the stability and reliability of the system. A converter output voltage is processed and compared to a control voltage to generate buck and boost comparator output signals. The buck and boost comparator output signals are provided to control logic, which generates switch control signals, which are provided to the DC-DC converter to establish buck mode, boost mode, or pass-through mode.

Abstract: An optical signal module including a driver and an optical signal module. The driver includes a differential pair configured to receive and process an input signal to create a drive signal. A modulation current source provides a modulation current to the differential pair. One or more termination resistors connected to the differential pair for impedance matching. A first switch, responsive to a first control signal, maintains charge on a charge storage device. The optical signal module includes an optical signal generator arranged between a supply voltage node and a bias current node. The optical signal generator receives the drive signal and generates an optical signal representing the input signal. A second switch is between a supply voltage node the bias current node. The second switch, responsive to second control signal, selectively establishes a short between the supply voltage node the bias current node.

Abstract: A system is disclosed to automatically establish proper biasing for light sources in a color mixed projection system having multiple light sources which are active at the same time. Responsive to a feedback signal, a single DC-DC converter generates the bias voltage for the light sources. Comparators compare a headroom signal for each light source to a reference value to generate comparator output signals. The comparator output signals are processed by a channel selector and a digital filter/DAC module. The channel selector controls a switch to selectively provide and combine a headroom signal with an output of the digital filter/DAC module to create the feedback signal. By monitoring each headroom value, the bias voltage is adjusted, based on the feedback signal, until every headroom signal reaches the reference value thereby achieving sufficient biasing for every active light source in the color mixed projection system.