Method and apparatus to control a power converter having a low loop bandwidth
Granted: October 30, 2012
Patent Number:
8300434
An example controller includes a feedback sensor circuit that receives a feedback signal representative of an output of a power converter. A feedback sampling signal generator is coupled to generate a feedback sampling signal. The feedback sensor circuit samples the feedback signal in response to the feedback sampling signal. A state machine controls switching of a switch of a power converter circuit according to one of a plurality of operating condition states in response to the…
Cascaded PFC and resonant mode power converters
Granted: October 30, 2012
Patent Number:
8300429
A power supply includes a PFC (power factor correction) converter that has an input and an output. The PFC converter input is coupled to an input of the power supply. The power supply also includes a resonant mode converter that has an input and an output. The resonant mode converter input is coupled to the PFC converter output and the resonant mode output is coupled to an output of the power supply. A control unit is also included in the power supply and is coupled to receive a feedback…
Power converter with compensation circuit for adjusting output current provided to a constant load
Granted: October 23, 2012
Patent Number:
8294377
A power converter for constant loads includes an energy transfer element, a switch, a controller, and a compensation circuit. The energy transfer element is coupled to receive a rectified voltage having a non-blocked portion and a blocked portion, where an amount of the blocked portion corresponds to a phase angle. The controller is coupled to control switching of the switch to regulate an output current of the power converter in response to a plurality of signals. The plurality of…
Control arrangement for a PFC power converter
Granted: October 9, 2012
Patent Number:
8284571
In a PFC (power factor correction) control unit for controlling a PFC converter, a transconductance amplifier is coupled to receive a feedback signal representative of an output voltage of the PFC converter. The transconductance amplifier is coupled to generate an output error signal in response to the feedback signal. A PWM (pulse width modulated) converter is coupled to receive the output error signal, the PWM converter is coupled to generate a PWM signal in response to the output…
Method and apparatus for simplifying the control of a switch
Granted: October 2, 2012
Patent Number:
8278972
A circuit for use in a half bridge converter includes a high side switch coupled between a positive input terminal and a first terminal of a primary transformer winding. A low side switch is coupled between a negative input terminal and the first terminal. A first control circuit is coupled to the high side switch to sense a slope of a voltage across the high side switch while the high side switch is off to control the high side switch in response to the sensed slope across the high side…
Temperature independent reference circuit
Granted: October 2, 2012
Patent Number:
8278994
A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R1 and R2, and third and second temperature coefficients, TC3 and TC2, respectively. The resistance values being such that a temperature coefficient of a difference between the…
Method and apparatus for a control circuit with multiple operating modes
Granted: October 2, 2012
Patent Number:
8279627
An example controller for use in a power converter includes an oscillator and a logic circuit. The oscillator is to be coupled to a switch of the power converter and determines a switching cycle period of the switch. The logic circuit is also to be coupled to the switch to control a duty cycle of the switch in response to a magnitude of a feedback signal to regulate an output of the power converter. The logic circuit controls the duty cycle of the switch such that a control loop gain of…
Flyback converter with forward converter reset clamp
Granted: October 2, 2012
Patent Number:
8279636
A power supply includes a first power converter, a second power converter, and a clamp reset circuit. The clamp reset circuit is electrically coupled to other components within the first power converter and the second power converter. A clamp standby connection can be provided to electrically couple the clamp reset circuit to components comprising the second power converter. The clamp reset circuit is coupled to reduce magnetizing energy of a transformer of the first power converter and…
Method and apparatus to select a parameter/mode based on a measurement during an initialization period
Granted: October 2, 2012
Patent Number:
8279643
An integrated circuit includes a threshold detection circuit that is coupled to measure a signal from a first resistive external circuit coupled between a fourth external terminal of the integrated circuit and a first external terminal of the integrated circuit during a duration of an initialization period after the fourth external terminal has been charged to a supply threshold value. A regulator circuit is coupled to charge the fourth external terminal to the supply threshold value…
Control arrangement for a resonant mode power converter
Granted: September 25, 2012
Patent Number:
8274799
A resonant mode power converter is controlled with a control unit including a current limiting circuit coupled to receive a first current representative of a power converter output and a second current generated in response to a reference voltage. The current limiting circuit is coupled to limit the first current in response to the second current. An oscillator is coupled to receive the first current to generate a control signal having a control frequency in response to the first…
Electronic circuit control element with tap element
Granted: September 11, 2012
Patent Number:
8264858
A technique for controlling a power supply with power supply control element with a tap element. An example power supply control element includes a power transistor that has first and second main terminals, a control terminal and a tap terminal. A control circuit is coupled to the control terminal. The tap terminal and the second main terminal of the power transistor are to control switching of the power transistor. The tap terminal is coupled to provide a signal to the control circuit…
Method of fabricating a deep trench insulated gate bipolar transistor
Granted: August 21, 2012
Patent Number:
8247287
In one embodiment, a method comprises forming an epitaxial layer over a substrate of an opposite conductivity type, the epitaxial layer being separated by a buffer layer having a doping concentration that is substantially constant in a vertical direction down to the buffer layer. A pair of spaced-apart trenches is formed in the epitaxial layer from a top surface of the epitaxial layer down at least into the buffer layer. A dielectric material is formed in the trenches over the first and…
Power factor correction converter control offset
Granted: August 21, 2012
Patent Number:
8248051
An apparatus includes a control unit to generate a control signal to control a duty cycle of a PWM switching signal that controls a switch in a PFC converter. The control unit includes a PWM converter to produce a PWM signal responsive to an output voltage of the PFC converter. A switching circuit switches a current representing an input current of the PFC converter in response to the PWM signal. A circuit generates the control signal in response to the switched current. The control unit…
Off-line converter with digital control
Granted: August 21, 2012
Patent Number:
8248053
A circuit for regulating the level at a power converter output is disclosed. An example circuit includes an input for receiving a feedback signal. The feedback signal has a first feedback state that represents a level that is above a threshold level and a second feedback state that represents a level that is below the threshold level. An oscillator is included that provides an oscillation signal that cycles between two states. A switch having a first terminal, a second terminal and a…
Dimming control for a switching power supply
Granted: August 14, 2012
Patent Number:
8242766
A controller for dimming control of a switching power supply includes a phase angle measurement block and a drive logic block. The phase angle measurement block is to be coupled to receive an input sense signal. The phase angle measurement block generates a phase angle signal representative of a phase angle of an input voltage of the power supply in response to the input sense signal. The drive logic block is to be coupled to control switching of a switch included in the power supply.…
Method and apparatus for pulse width modulation
Granted: August 14, 2012
Patent Number:
8242825
An integrated control circuit according to aspects of the present invention includes a capacitor to develop a first current during a first time duration in response to a charge current and to develop a second voltage during a second time duration in response to a discharge current. A comparator is also included and is coupled to the capacitor to indicate when the voltage on the capacitor reaches the second voltage. A control logic sets a duty ratio of a periodic output signal in response…
Flyback power supply with forced primary regulation
Granted: August 14, 2012
Patent Number:
8243477
A controller that forces primary regulation is disclosed. An example controller includes a switched element to be coupled to a second winding of an energy transfer element of a power supply. A secondary control circuit is coupled to the switched element. The secondary control circuit is to be coupled across an output of the second winding to switch the switched element in response to a difference between an actual output value at the output of the second winding and a desired output…
Method and apparatus for limiting maximum output power of a power converter
Granted: August 14, 2012
Patent Number:
8243478
An example power converter includes an energy transfer element, a switch, a controller, and a current offset circuit. The controller switches the switch between an ON state and an OFF state to regulate the output of the power converter and is adapted to terminate the ON state of the switch in response to a switch current flowing through the switch reaching a switch current threshold. The current offset circuit is coupled to the input to be directly powered from an input voltage of the…
Method and apparatus for a control circuit responsive to an impedance coupled to a control circuit terminal
Granted: August 14, 2012
Patent Number:
8243480
An example power supply controller includes a regulation circuit, a current sense circuit, and a response circuit. The regulation circuit is coupled to regulate a sense terminal to a voltage level. The current sense circuit is coupled to the sense terminal to sense a current through the sense terminal a measurement delay period after a magnitude of the current through the sense terminal reaches a first threshold current level. The response circuit is coupled to the sense circuit and is…
Method and apparatus for controlling a circuit with a high voltage sense device
Granted: August 7, 2012
Patent Number:
8236656
A high-voltage junction field-effect transistor (JFET) includes a semiconductor substrate, a well region, first, second, and third doped regions, and first, second, and third terminals. The first doped region is disposed in the well region and the second dope region is laterally displaced from the well region. The third doped region is disposed in the well region between the first and second doped regions. A portion of the well region is substantially depleted of free charge carriers…
