Abstract: A resonant power converter controller comprising a control circuit configured to turn on a synchronous rectifier (SR) in response to a count of a number of times a drain voltage of the SR crosses below a turn on threshold based on a stored count and turns off the SR when the drain voltage crosses above a turn off threshold. The control circuit comprises a first comparator configured to generate a first detection signal in response to the drain voltage being less than the turn on threshold. A first turn on detection circuit generates a first turn on signal when the count reaches the stored count. A first turn off signal is generated in response to the drain voltage being greater than the turn off threshold. A drive circuit turns on and off the SR in response to the first turn on signal and the first turn off signal.

Abstract: A power converter controller includes a control loop clock generator that generates a switching frequency signal in response to a sense signal representative of a characteristic of the power converter, a load signal responsive to an output load, and a limit signal representative of a maximum length of a current half cycle of the switching frequency signal. A comparator generates an enable signal in response to the load signal and a load threshold. A limit control generates the limit signal in response to the enable signal and the switching frequency signal. A rate of change of half cycles of the switching frequency signal is controlled in response to the limit signal. A request transmitter generates a request signal in response to the switching frequency signal to control switching of a switching circuit coupled to the energy transfer element and an input of the power converter.

Abstract: A controller for use in a power converter includes a control loop clock generator that is coupled to generate a switching frequency signal in response to a sense signal representative of a characteristic of the power converter, a load signal responsive to an output load of the power converter, and a hard switch sense output. A hard switch sense circuit is coupled to generate the hard switch sense output in response to the switching frequency signal and a rectifier conduction signal that is representative of a polarity of an energy transfer element of the power converter. A request transmitter circuit is coupled to generate a request signal in response to the switching frequency signal to control switching of a switching circuit coupled to an input of the energy transfer element of the power converter.

Abstract: A power converter controller includes a control loop clock generator that generates a switching frequency signal in response to a sense signal representative of a characteristic of the power converter, a load signal responsive to an output load, and a limit signal representative of a maximum length of a current half cycle of the switching frequency signal. A comparator generates an enable signal in response to the load signal and a load threshold. A limit control generates the limit signal in response to the enable signal and the switching frequency signal. A rate of change of half cycles of the switching frequency signal is controlled in response to the limit signal. A request transmitter generates a request signal in response to the switching frequency signal to control switching of a switching circuit coupled to the energy transfer element and an input of the power converter.

Abstract: A controller for use in a power converter includes a control loop clock generator that is coupled to generate a switching frequency signal in response to a sense signal representative of a characteristic of the power converter, a load signal responsive to an output load of the power converter, and a hard switch sense output. A hard switch sense circuit is coupled to generate the hard switch sense output in response to the switching frequency signal and a rectifier conduction signal that is representative of a polarity of an energy transfer element of the power converter. A request transmitter circuit is coupled to generate a request signal in response to the switching frequency signal to control switching of a switching circuit coupled to an input of the energy transfer element of the power converter.

Abstract: A resonant power converter controller comprising a control circuit configured to turn on a synchronous rectifier (SR) in response to a count of a number of times a drain voltage of the SR crosses below a turn on threshold based on a stored count and turns off the SR when the drain voltage crosses above a turn off threshold. The control circuit comprises a first comparator configured to generate a first detection signal in response to the drain voltage being less than the turn on threshold. A first turn on detection circuit generates a first turn on signal when the count reaches the stored count. A first turn off signal is generated in response to the drain voltage being greater than the turn off threshold. A drive circuit turns on and off the SR in response to the first turn on signal and the first turn off signal.

Abstract: A secondary controller including a control circuit coupled to a secondary switch of a power converter. The control circuit is coupled to receive a secondary switch voltage signal representative of the secondary switch, and turns ON the secondary in response in response to how many times the secondary switch voltage signal crosses below a turn on threshold to a limit set in a last half period. The control circuit turns OFF the secondary switch when the secondary switch voltage signal crosses above a turn off threshold.

Abstract: A secondary controller including a control circuit coupled to a secondary switch of a power converter. The control circuit is coupled to receive a secondary switch voltage signal representative of the secondary switch, and turns ON the secondary in response in response to how many times the secondary switch voltage signal crosses below a turn on threshold to a limit set in a last half period. The control circuit turns OFF the secondary switch when the secondary switch voltage signal crosses above a turn off threshold.

Abstract: A Galvanically Isolated Amplifier (GIA) includes an isolation barrier to galvanically isolate high voltage circuitry from low voltage circuitry. The high voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to ground potential at a first potential relative to the ground potential. The low voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to the ground potential at a second potential, the second potential being smaller than the first potential. A Radio Frequency (RF) carrier is digitally Phase Shift Keying (PSK) modulated for transmission across the isolation barrier. The unmodulated RF carrier could also be transmitted across the isolation barrier. PSK modulation could be applied to the RF carrier based on a test waveform to generate a PSK-modulated test signal for transmission while a voltage transient is applied between the high voltage circuitry and the low voltage circuitry.

Abstract: A Galvanically Isolated Amplifier (GIA) includes an isolation barrier to galvanically isolate high voltage circuitry from low voltage circuitry. The high voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to ground potential at a first potential relative to the ground potential. The low voltage circuitry has at least two voltage supply rails, with the voltage supply rail closest to the ground potential at a second potential, the second potential being smaller than the first potential. A Radio Frequency (RF) carrier is digitally Phase Shift Keying (PSK) modulated for transmission across the isolation barrier. The unmodulated RF carrier could also be transmitted across the isolation barrier. PSK modulation could be applied to the RF carrier based on a test waveform to generate a PSK-modulated test signal for transmission while a voltage transient is applied between the high voltage circuitry and the low voltage circuitry.

Abstract: An electrical circuit and method includes a transmitter in a first power domain with a first supply voltage referenced to a first voltage reference. The transmitter has an oscillator generating a first carrier signal, and an analog modulator receiving an input sensor signal and the first carrier signal and generating a modulated carrier signal. A receiver is in a second power domain with a second supply voltage referenced to a second voltage reference. The second voltage reference is different from the first voltage reference. The receiver includes a demodulator that receives and demodulates the modulated carrier signal and generates an output sensor signal. At least one coupler includes a pair of galvanically isolated elements with one galvanically isolated element in each of the first and second power domains. The modulated carrier signal couples from the first power domain to the second power domain through the at least one coupler.

Abstract: An electrical circuit and method includes a transmitter in a first power domain with a first supply voltage referenced to a first voltage reference. The transmitter has an oscillator generating a first carrier signal, and an analog modulator receiving an input sensor signal and the first carrier signal and generating a modulated carrier signal. A receiver is in a second power domain with a second supply voltage referenced to a second voltage reference. The second voltage reference is different from the first voltage reference. The receiver includes a demodulator that receives and demodulates the modulated carrier signal and generates an output sensor signal. At least one coupler includes a pair of galvanically isolated elements with one galvanically isolated element in each of the first and second power domains. The modulated carrier signal couples from the first power domain to the second power domain through the at least one coupler.

Abstract: A hybrid junction device formed by an intermediate conductor located between and spaced from an outer conductor and a central conductor. The conductors are all about .lambda./4 in length. A first port is connected between the central conductor and the outer conductor at one end of the device and a second port is connected between the intermediate conductor and the outer conductor at the other end of the device. A third port is connected between the intermediate and the outer conductor at one end of the device while a fourth port is connected between the central conductor and outer conductor at the other end. The conductors may be co-axial or stripline type conductors.

Abstract: An antennae feed or take-off for a plurality of antennae where the transmission line, connecting the antennae to the termination of the line, is in a closed loop whereby signal flows either direction and transmission line phase shifts are largely compensated.