Adaptive biasing for integrated circuits
Granted: March 15, 2016
Patent Number:
9287784
Methods and apparatuses are disclosed for generating an adjustable bias current. The value of the adjustable bias current may be determined based in part on an error signal representative of a difference between an actual output value and a desired output value of a power converter. When the error signal is below a lower threshold voltage, the adjustable bias current may be set to a first value. When the error signal is above an upper threshold voltage, the adjustable bias current may be…
Light driver control system
Granted: March 8, 2016
Patent Number:
9282602
A system for controlling a light source includes a control circuit to be coupled to an ac source to receive an ac signal. The control circuit includes an input controller coupled to receive an input control signal and dimming command circuitry coupled to the input controller and coupled to receive the ac signal. The dimming command circuitry is coupled to remove one or more portions of a predetermined duration from the ac signal followed by a substantially full ac signal in response to…
Receive circuit for use in a power converter
Granted: March 1, 2016
Patent Number:
9276479
A receive circuit for use in a power converter controller includes a first amplifier coupled to receive an input pulse. A second amplifier is coupled to a first output of the first amplifier. The first output is coupled to be responsive to the input pulse and to a second output of the second amplifier. An output circuit is coupled to generate an output signal in response to the second output.
Switch mode power converters using magnetically coupled galvanically isolated lead frame communication
Granted: March 1, 2016
Patent Number:
9275946
An integrated circuit package for use in a switch mode power converter includes a portion of a lead frame disposed within an encapsulation. The lead frame includes a first conductor having an inner conductive loop disposed within the encapsulation, and a second conductor galvanically isolated from the first conductor having an outer conductive loop disposed within the encapsulation and magnetically coupled to the first conductive loop to provide a communication link between the first and…
Line ripple compensation for shimmerless LED driver
Granted: February 23, 2016
Patent Number:
9271352
A power converter controller includes an oscillator, a drive circuit, and a frequency modulator. The drive circuit receives a clock signal from the oscillator and generates a drive signal in response thereto to control switching of a switch of the power converter. The frequency modulator controls the frequency of the clock signal in response to an inductor voltage across an inductor of the energy transfer element to reduce a peak-to-peak ripple value in an output current of the power…
Single-stage power supply with power factor correction and constant current output
Granted: February 16, 2016
Patent Number:
9263958
An example power supply includes an energy transfer element, a switch, and a controller. The switch is coupled to the energy transfer element to control a transfer of energy from an input to a galvanically isolated output of the power supply. The controller includes a delayed ramp generator, an integrator, an arithmetic operator, and a drive signal generator. The integrator generates a first signal responsive to integrating an input current of the power supply. The arithmetic operator…
Method and apparatus for determining zero-crossing of an ac input voltage to a power supply
Granted: February 16, 2016
Patent Number:
9263934
An example controller for a power supply includes a first circuit and a drive signal generator. The first circuit receives a first signal representative of a switch current flowing through a switch of the power supply and then generates a second signal in response the switch current not reaching a current threshold within an amount of time. The second signal indicates when a dimming circuit at an input of the power supply is utilized. The drive signal generator generates a drive signal…
Power integrated circuit with incorporated sense FET
Granted: February 16, 2016
Patent Number:
9263564
In one embodiment, a power integrated circuit device includes a main lateral high-voltage field-effect transistor (HVFET) and an adjacently-located lateral sense FET, both of which are formed on a high-resistivity substrate. A sense resistor is formed in a well region disposed in an area of the substrate between the HVFET and the sense FET. A parasitic substrate resistor is formed in parallel electrical connection with the sense resistor between the source regions of the HVFET and the…
Power supply circuit with a control terminal for different functional modes of operation
Granted: February 2, 2016
Patent Number:
9253832
A method of operation for flyback power converter includes operating a controller of the flyback power converter in a regulation mode when a control signal is below a first threshold. The control signal is provided as an input to a terminal of the flyback power converter. When the control signal is below a second threshold and above the first threshold, the controller is operated in a limiting mode. The controller is operated in an external command mode when the control signal is below a…
Switched mode power converter controller with ramp time modulation
Granted: January 26, 2016
Patent Number:
9246392
A controller for use in a power converter includes a drive circuit coupled to generate a drive signal to control switching of a power switch to control a transfer of energy from a power converter input to a power converter output. The controller also includes an input for receiving an enable signal including enable events responsive to the power converter output. The drive circuit is coupled to turn ON the power switch in response to the enable events and turn OFF the power switch in…
Static discharge system
Granted: January 26, 2016
Patent Number:
9245879
A semiconductor circuit includes a three-terminal high voltage semiconductor device, a charge distribution structure and a static discharge system. The charge distribution structure has a plurality of conductors with a floating potential. The charge distribution structure is capacitively coupled to a first terminal of the semiconductor device. The static discharge system removes charge that accumulates on at least a subset of the conductors. The static discharge system removes the charge…
Overvoltage protection using a tapFET
Granted: December 22, 2015
Patent Number:
9219420
Systems and processes for protecting a power converter against overvoltage conditions are disclosed. In one example, an overvoltage protection circuit may be used to sense the input voltage of the power converter to determine whether the input voltage is greater than a threshold value. In response to determining that the sensed input voltage is greater than the threshold value, an input capacitance and/or capacitance of an EMI filter of the power converter may be discharged to ground or…
Method and apparatus to reduce audio frequencies in a switching power supply
Granted: December 22, 2015
Patent Number:
9219418
An example power supply regulator includes an energy transfer element, a switch, and a controller. The controller includes a switch signal generator, a modulation circuit, and a multi-cycle modulator circuit. The modulation circuit modulates the period of a modulation switching signal when an equivalent switching frequency is greater than a reference frequency and fixes the switching period when the equivalent switching frequency is less than the reference frequency. The multi-cycle…
Trailing edge detector using current collapse
Granted: December 15, 2015
Patent Number:
9214851
A controller for a power converter compares a voltage sense signal to a first reference and compares a current sense signal to a current sense signal. The voltage sense signal is representative of an input voltage of the power converter. The current sense signal is representative of a current through the power converter. A slope of the voltage sense signal is measured over time. An edge detection is asserted by the controller when (1) the voltage sense signal is larger than the first…
Bleeder circuit for use in a power supply
Granted: December 8, 2015
Patent Number:
9210744
A bleeder circuit for use in a power supply of a lighting system includes a first terminal to be coupled to a first input of the power supply. A second terminal is to be coupled to a second input of the power supply. An edge detection circuit is coupled between the first and second terminals of the bleeder circuit. The edge detection circuit is coupled to output an edge detection signal in response to an input signal between the first and second inputs. A variable current circuit is…
Digital-to-analog converter circuit for use in a power converter
Granted: December 1, 2015
Patent Number:
9203424
A digital-to-analog converter circuit includes an input to receive a digital input signal having multiple bits. A modulation circuit is coupled to respond to less significant bits of the digital input signal by outputting a modulation signal that alternates between a logic low level and a logic high level. A digital-to-analog circuit is configured to convert more significant bits of the digital input signal to a first analog level. The digital-to-analog circuit is configured to alternate…
Isolation testing of semiconductor devices
Granted: November 17, 2015
Patent Number:
9188634
One example apparatus for isolation testing of semiconductor devices may include an interface portion for making electrical contact with packaged semiconductor devices under test. The interface portion may include an insulating support configured and dimensioned to support multiple semiconductor device packages, each semiconductor device package having a plurality of electrical contacts. The interface portion may further include a first electrically conductive surface to electrically…
Transverse shield wire for energy transfer element
Granted: November 3, 2015
Patent Number:
9177714
Energy transfer elements having a shield to reduce EMI while maintaining a low profile are disclosed. In one example, the transformer may include a transverse shield wire that may be utilized to keep displacement current within the energy transfer element. While windings of the energy transfer element are generally wound axially around the axis of a bobbin in a direction generally perpendicular to the axis of the bobbin, the transverse shield wire may be placed on the bobbin extending…
Phase angle measurement of a dimming circuit for a switching power supply
Granted: November 3, 2015
Patent Number:
9178432
An example switched mode power supply includes a timer, a threshold adjust circuitry, a comparator, and a control circuitry. The timer times a duration between crossings of a phase-dimmed signal across a first threshold. The threshold adjust circuitry adjusts a second threshold representative of a desired output of the switched mode power supply, where the second threshold is adjusted responsive to the timed duration between crossings. The comparator compares a feedback signal with the…
Charging circuit for a power converter controller
Granted: November 3, 2015
Patent Number:
9178411
A controller includes a first controller terminal, a second controller terminal, a first p-channel metal-oxide-semiconductor field-effect transistor, and a second pMOS transistor. The first controller terminal is to be coupled to a bypass capacitor coupled to a secondary side of an isolated power converter. The second controller terminal to be coupled to an output node of the secondary side. The first pMOS transistor includes a first source terminal coupled to the second controller…
