Pre-distortion of sensed current in a power factor correction circuit
Granted: July 14, 2020
Patent Number:
10715033
A method of enhancing a power factor during a half-line cycle of a power factor correction (PFC) converter includes generating an input voltage signal representative of a value of an input voltage of the PFC converter. A variable multiplication factor is adjusted to be greater than one for a first part of the half-line cycle and less than one for a second part of the half-line cycle. A pre-distortion signal is generated to be representative of the value of the input voltage of the PFC…
Techniques for controlling a power converter using multiple controllers
Granted: June 23, 2020
Patent Number:
10693380
A controller configured for use with a power converter and a power switch comprising a primary controller coupled to the power converter and configured to provide a switch drive signal to control switching of the power switch to transfer energy from a primary side to a secondary side of the power converter. A primary switching pattern circuit is configured to provide a primary switching pattern to operate the primary controller in a first mode of operation and a primary switch control…
Multi-stage gate turn-off with dynamic timing
Granted: June 9, 2020
Patent Number:
10680604
A turn-off circuit for a semiconductor switch includes an element having a variable resistance coupled to a control input of the semiconductor switch, a circuit for generating a control-input reference signal, and a control circuit coupled to adjust a resistance of the element having a variable resistance in response to the control-input reference signal in a closed control loop in order to turn off the semiconductor switch.
Asymmetrical plug technique for GaN devices
Granted: May 26, 2020
Patent Number:
10665463
A method of forming one or more contact regions in a high-voltage field effect transistor (HFET) includes providing a semiconductor material, including a first active layer and a second active layer, with a gate dielectric disposed on a surface of the semiconductor material. A first contact to the semiconductor material is formed that extends through the second active layer into the first active layer, and a passivation layer is deposited, where the gate dielectric is disposed between…
Biasing circuit for switch
Granted: May 5, 2020
Patent Number:
10644688
A driver circuit for use in a controller includes a signal generator coupled to generate a first control signal and a second control signal in response to a drive signal that is coupled to control switching of a secondary switch that is to be coupled to the driver circuit and referenced to a reference voltage that is greater than a ground reference voltage. A second switch is coupled to be controlled by the second control signal such that the reference voltage is substantially applied to…
Protective insulator for HFET devices
Granted: April 21, 2020
Patent Number:
10629719
An HFET includes a first and second semiconductor material. A first composite passivation layer includes a first insulation layer and a first passivation layer, and the first passivation layer is disposed between the first insulation layer and the second semiconductor material. The HFET includes a second passivation layer, where the first insulation layer is disposed between the first passivation layer and the second passivation layer. A gate dielectric is disposed between the second…
Method and apparatus for implementing a power converter input terminal voltage discharge circuit
Granted: March 31, 2020
Patent Number:
10608525
A circuit for use in a power converter includes a control circuit capable of detecting whether an AC voltage source is coupled to an input of the power converter, and whether the AC voltage source is uncoupled from the input within a first period of time. A control circuit is coupled to drive a switch in a first operating mode when the control circuit detects that the AC voltage source is coupled to the input, and drive the switch in a second operating mode when the control circuit…
Current damping circuit
Granted: March 10, 2020
Patent Number:
10587186
A circuit for shaping an input current of a switching power converter. The circuit is a power factor circuit comprising an input to be coupled to receive a rectified line signal, an output, a resistance coupled to resist a flow of current from the input to the output. The resistance has a first value and a switch coupled in parallel with the resistance and coupled to switch from a less conductive state into a more conductive state in response to the flow of current through the input, and…
Modulating jitter frequency as switching frequency approaches jitter frequency
Granted: March 10, 2020
Patent Number:
10585444
A controller for use in a power converter including a jitter generator circuit coupled to receive a drive signal from a switch controller and generate a jitter signal. The jitter signal is a modulated jitter signal when the drive signal is below a first threshold frequency. The switch controller is coupled to a power switch coupled to an energy transfer element. The switch controller is coupled to receive a current sense signal representative of a current through the power switch. The…
Communications using an inductive coupling
Granted: February 25, 2020
Patent Number:
10574302
A controller for a semiconductor switch is described that includes a transmitter and a receiver that communicate across galvanic isolation using an inductive coupling. An example controller includes first circuitry referenced to a first reference potential, second circuitry referenced to a second reference potential and galvanically isolated from the first circuitry, and an inductive coupling galvanically isolating the first circuitry and the second circuitry. The inductive coupling…
BJT driver with dynamic adjustment of storage time versus input line voltage variations
Granted: February 25, 2020
Patent Number:
10574145
A method of dynamically adjusting a storage time of a bipolar junction transistor (BJT) in a switched mode power converter during a switching cycle includes generating a storage time reference signal responsive to an input voltage signal. A collector off signal is generated responsive to a comparison of a current sense signal to a collector off reference threshold signal. The current sense signal is representative of a switch current of the BJT. A base off reference threshold signal is…
Control of secondary switches based on secondary winding voltage in a power converter
Granted: February 4, 2020
Patent Number:
10554136
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…
Idle ring detection for a multi-output power converter
Granted: February 4, 2020
Patent Number:
10554134
A controller for use in a power converter with multiple outputs includes a discharge detect circuit coupled to receive a voltage signal from a transformer winding of the power converter to output a discharge signal in response to the voltage signal. A multi-output signal process and interface block is coupled to output request signals to the output selection drive and idle ring visibility logic circuit. An output selection drive and idle ring visibility logic circuit is coupled to…
Apparatus and methods for controlling a switch mode power converter using a duty cycle state machine
Granted: December 10, 2019
Patent Number:
10505458
A power conversion system includes a switch mode power converter including a switch coupled to regulate an output voltage to a regulation value in response to a feedback signal. A controller is coupled to deliver a gate drive signal to the switch during an enabled control condition. The controller is further coupled to inhibit the gate drive signal to the switch during an inhibited control condition. A duty cycle state machine included in controller is coupled to adjust a duty cycle of…
Voltage-to-current transconductance operational amplifier with adaptive biasing
Granted: December 3, 2019
Patent Number:
10498300
An IC for power conversion includes bias circuitry that generates one or more bias voltages. An adaptive biasing circuit adaptively shifts an input signal having a negative value to a positive value. An operational transconductance amplifier (OTA) receives a supply bias current and the first and second bias voltages. The OTA has first and second input terminals coupled to the input signal and ground, respectively. The OTA has first and second transistors coupled to the first and second…
High side signal interface in a power converter
Granted: December 3, 2019
Patent Number:
10498244
A controller for use in a power converter of a motor drive includes a control circuit configured to turn ON a high side switch by sinking a current of an ON signal. A high side signal interface circuit is coupled to receive the ON signal to generate a drive signal to control switching of the high side switch in a presence of a common mode signal caused by slewing at a half bridge node. The high side signal interface circuit includes a common mode cancellation circuit coupled to provide a…
Closed loop foldback control
Granted: November 26, 2019
Patent Number:
10491126
A controller for use in a power converter includes comparator coupled to generate a regulation signal in response to a regulation reference and an output sense signal. The output sense signal is representative of an output of the power converter. A drive signal generator is coupled to the comparator to generate a drive signal to control switching of a power switch of the power converter in response to the regulation signal. The drive signal generator is further coupled to generate an…
Integrated resistor for semiconductor device
Granted: November 26, 2019
Patent Number:
10490548
A heterostructure semiconductor device includes first and second active areas, each electrically isolated from one another, and each including first and second active layers with an electrical charge disposed therebetween. A power transistor is formed in the first active area, and an integrated gate resistor is formed in the second active area. A gate array laterally extends over the first active area of the power transistor. First and second ohmic contacts are respectively disposed at…
Method and apparatus for a control circuit with multiple operating modes
Granted: October 29, 2019
Patent Number:
10461647
A controller includes an oscillator coupled to a switch to determine a time at which the switch is turned on. The oscillator includes a capacitor, a charging current source and a discharging current source coupled to charge and discharge the capacitor. A time period for the capacitor to charge and discharge between first and second voltage levels is a time period of a switching cycle. A duty cycle mode control circuit is coupled to operate in a first duty control mode in response to a…
Clamp for a hybrid switch
Granted: October 29, 2019
Patent Number:
10461740
A switch having a drain terminal, a source terminal and a control terminal. The switch comprises a normally-on device including a first terminal, a second terminal, and a control terminal, a normally-off device including a first terminal, a second terminal, and a control terminal, and a clamp circuit. The first terminal of the normally-on device is the drain terminal of the switch and the control terminal of the normally-on device is coupled to the source terminal of the switch. The…
