Patent classifications
H02M3/33553
Apparatus and method for adaptively setting the proper range for the VCM control variable based upon clipping of the main regulation loop
A power converter including: a dual output resonant converter including a first output, a second output, a common mode control input, and a differential mode control input, wherein a voltage/current at the first output and a voltage/current at the second output are controlled in response to a common mode control signal received at the common mode control input and a differential mode control signal received at the differential mode control input; a dual output controller including a first error signal input, a second error signal input, a common mode control output, and a differential mode control output, wherein the dual output controller is configured to generate the common mode control signal and the differential mode control signal in response to a first error signal received at the first error signal input and a second error signal received at the second error signal input, wherein the first error signal is a function of the voltage/current at the first output and the second error signal is a function of the voltage/current at the second output, and wherein the common mode control signal is output from the common mode control output and the differential mode control signal is output from the differential mode control output; and a common mode signal offset circuit configured to generate a common mode signal offset signal wherein the common mode signal offset signal adjusts a difference in output power between the first output and the second output of the dual output resonant converter.
Test system and test method for a voltage regulator with multi-mode control
A test method of a voltage regulator having a plurality of parameters that need to be set, the test method includes: receiving a user requirement on a computer; generating a plurality of setting combinations of the plurality of parameters, the plurality of parameters has different combination of values in different setting combinations; downloading the plurality of setting combinations to the voltage regulator via a first I/O bus and configuring the voltage regulator with each setting combination; configuring communication between a controller provided by the computer and measurement devices; executing the communication between the controller and the measurement devices via a second I/O bus; and displaying test result of each configured voltage regulator on the computer.
Capacitively isolated feedback circuits and regulated power supplies incorporating the same
A regulated power supply includes a capacitively isolated feedback circuit and a pulse width modulator (PWM) operable to produce a plurality of pulses at an output and receive a sampled voltage at a feedback input thereof. The capacitively isolated feedback circuit includes a capacitively isolated gate drive circuit directly coupled to the PWM output and configured to produce a plurality of isolated pulses from the plurality of pulses received from the PWM output. The capacitively isolated feedback circuit also includes a forward converter feedback circuit, which includes a switching transistor directly coupled to the capacitively isolated gate drive circuit for receiving the plurality of isolated pulses at a gate of the switching transistor and a feedback transformer directly coupled to the PWM for providing the sampled voltage at the feedback input. The plurality of isolated pulses causes the feedback transformer to sample a load voltage as the sampled voltage.
POWER SUPPLY DEVICE FOR SUPPRESSING NOISE
A power supply device for suppressing noise includes a first bridge rectifier, a second bridge rectifier, a coupling inductive element, a first power switch element, a first output stage circuit, a switch circuit, a transformer, a second output stage circuit, and an auxiliary control circuit. The first bridge rectifier and second bridge rectifier generate a first rectified voltage and a second rectified voltage according to a first input voltage and a second input voltage. The coupling inductive element receives the first rectified voltage and the second rectified voltage. The switch circuit generates a control voltage. The second output stage circuit generates an output voltage. The auxiliary control circuit includes a second power switch element. The second power switch element is coupled to the coupling inductive element, and is selectively enabled or disabled according to the control voltage.
MULTI-MODE HYBRID CONTROL DC-DC CONVERTING CIRCUIT AND CONTROL METHOD THEREOF
A multi-mode hybrid control DC-DC converting circuit has a switching power converter and a microcontroller. The switching power converter has a transformer and a switching switch. The switching switch is connected to a primary-side winding of the transformer in series. The microcontroller is connected to the switching power converter and a control terminal of the switching switch. The microcontroller sets multiple thresholds according to an input voltage of the switching power converter, and determines whether a feedback voltage of the switching power converter is higher or lower than each one of the thresholds to perform a variable-frequency mode, a constant-frequency mode, or a pulse-skipping mode. The microcontroller outputs a driving signal to the switching switch and correspondingly adjusts a frequency of the driving signal according to the variable-frequency mode, the constant-frequency mode, or the pulse-skipping mode which is performed.
STARTUP CIRCUIT FOR A FLYBACK CONVERTER
A converter includes a power stage to provide a current through a primary winding of a transformer in response to a PWM signal and to induce a current in a secondary winding of the transformer to generate an output voltage. The power stage has a switching terminal. The converter also includes a controller, a clamp circuit, and an impedance device. The controller includes a first transistor coupled with a second transistor to initiate an operational voltage during a startup mode and to provide a control voltage based on an amplitude of a switching voltage at the switching terminal during a switching mode. The clamp circuit couples between the control input of the first transistor and a reference terminal and clamps a voltage at the first control input responsive to the switching voltage exceeding a clamp voltage. The impedance device couples between the switching terminal and the clamp circuit.
Resonant converter
This disclosure describes systems, methods, and apparatus for controlling a voltage provided to a plurality of configurable output modules using a resonant converter, the resonant converter comprising: an inverter circuit; a resonant capacitor bridge coupled across the inverter circuit; N groups of output modules, each of the N groups comprising terminals configured for coupling to up to M output modules, the output modules each comprising: a transformer having a primary and a secondary; and a rectified output coupled to the secondary and configured for coupling to a load; and a resonant inductor network configured to be coupled between the resonant capacitor bridge and the primaries of the transformers, the resonant inductor network comprising: at least one parallel inductor; and N parallel branches arranged in parallel and each branch comprising a series inductor, each of the series inductors configured for transformer-coupling to up to M output modules.
Control circuit for a power converter
The invention provides a control circuit for controlling the operation of a power converter having a switch connected to an output of the power converter, said control circuit comprising a first amplifier for sensing an output voltage of the power converter and a second amplifier configured to derive a frequency compensated error signal output, to provide a frequency control compensation loop to an input of the power converter and the output of the second amplifier is connected to the switch of the power converter.
Forward DC-DC ZVS converter and control scheme
The proposed solution allows a forward DC-DC converter's isolated transformer to resonant reset and the forward DC-DC converter to operate in ZVS condition regardless of whether the output inductor current is in DCM or CCM. To compare with a regular forward DC-DC converter, the output isolated transformer has an extra reset winding Nt in addition to the regular primary and secondary windings Np and Ns. Based on the rule of the magnetic flux remaining unchanged for the forward output isolated transformer, it is the extra reset winding Nt, a resonant capacitor Cr, an additional MOS Q2 and the related control function block M that allow the forward output isolated transformer to finish resonant reset and the primary main power MOS Q1 to operate in ZVS. The magnetizing current of the forward output isolated transformer is fully utilized, and regardless of whether the resonant reset circuit is on the primary or the secondary, the magnetizing current can enable the forward output isolated transformer to resonant reset and serve as the main power MOS Q1 operation in ZVS.
LOAD DRIVING DEVICE, AND LIGHTING APPARATUS AND LIQUID CRYSTAL DISPLAY DEVICE USING THE SAME
A light emitting load driving device includes a first constant current source structured to be serially connected to a first light emitting load group; a second constant current source structured to be serially connected to a second light emitting load group; a first load connection terminal structured to be connected to the first light emitting load group; a second load connection terminal structured to be connected to the second light emitting load group; and a control circuit structured to be supplied a first voltage applied to the first load connection terminal, a second voltage applied to the second load connection terminal, and a reference voltage applied to the control circuit, wherein the control circuit is structured to select a minimum voltage between the first voltage and the second voltage, and the control circuit is structured to equalize the minimum voltage and the reference voltage.