An electronic circuit comprises a first and second comparators and a first summer. The first comparator is configured to perform a first comparison to compare a first current reference signal with a signal representing an input current and configured to generate a first current error signal based on the first comparison. The second comparator is configured to perform a second comparison to compare a second current reference signal with the signal representing the input current and configured to generate a second current error signal based on the second comparison. The first summer is configured to adjust a first summer input error signal based on a second summer input error signal. The first summer input error signal is based on the first current error signal, and the second summer input error signal is based on the second current error signal.

Power converters with power factor correction circuits and controllers thereof that are configured to generate frequency-adjustable first and second pulsed signals having respective and complementary phases separated by an adjustable deadtime. For example, a power converter may be configured to receive an alternating current (AC) input signal and output a direct current (DC) output signal. The power converter may include at least one DC/DC converter and a power factor correction circuit. The power factor correction circuit may include a first switching transistor comprising a first gate; a second switching transistor in series with the first switching transistor and comprising a second gate; and a controller configured to generate first and second pulsed signals having respective and complementary phases and separated by an adjustable deadtime and apply the generated first and second pulsed signals to the first and second gates, respectively.

A switching control circuit for a power supply circuit, including: a first command value output circuit outputting a first command value; a correction circuit correcting the first command value, to output a second command value; a first timer circuit measuring a first time period starting from a first timing at which a transistor of the power supply circuit is turned on; and a driving signal output circuit outputting a driving signal to turn on the transistor in response to an inductor current of the power supply circuit reaching a predetermined value and the first time period having elapsed since the first timing, and outputting the driving signal to turn off the transistor based on the second command value. The correction circuit causes an on time period of the transistor to increase, when the first time period has elapsed since the first timing, after the inductor current reaches the predetermined value.

Power converters with power factor correction circuits and controllers thereof that are configured to generate frequency-adjustable first and second pulsed signals having respective and complementary phases separated by an adjustable deadtime. For example, a power converter may be configured to receive an alternating current (AC) input signal and output a direct current (DC) output signal. The power converter may include a transformer and a power factor correction circuit. The power factor correction circuit may include: a first switching transistor and a second switching transistor in series with the first switching transistor; and a controller configured to generate first and second pulsed signals having respective and complementary phases and separated by an adjustable deadtime and apply the generated first and second pulsed signals to the first and second transistors, respectively. A primary side of the transformer may be coupled to a node between the first and second switching transistors.

Power factor correction circuits and controllers thereof that are configured to generate frequency-adjustable first and second pulsed signals having respective and complementary phases separated by an adjustable deadtime. For example, a controller for a power factor correction circuit may include a comparator, a frequency controller, and a deadtime controller. The controller may be configured to: receive an input signal comprising a measured output voltage of the power factor correction circuit; compare, via the comparator, the measured output voltage with a set point, resulting in a difference between the measured output voltage and the set point; feed the difference into the frequency controller and adjust a frequency of the first and second pulsed signals based on an output of the frequency controller; and provide the difference to the deadtime controller and adjust the deadtime of the first and second pulsed signals based on an output of the deadtime controller.

A control circuit for a plurality of metal-oxide semiconductor field-effect transistors (MOSFETs) in a bridge circuit for rectifying an alternating current (AC) input to generate a direct-current (DC) output includes first and second high side controls and first and second low side controls for providing gate voltage signals to respective MOSFETs in the bridge circuit. Dead time controls are provided for establishing dead time intervals between activation of complementary MOSFETs in the bridge circuit. The low side controls provide gate voltage signals having sloped edges and the dead time controls include Zener diodes having reverse bias thresholds for determining the duration of the dead time intervals.

A method and a control circuit for driving an electronic switch coupled to an inductor in a power converter in successive drive cycles each including an on-time and an off-time are disclosed. Driving the electronic switch includes: measuring an inductor voltage during the on-time in a drive cycle in order to obtain a first measurement value; measuring the inductor voltage during the off-time in a drive cycle in order to obtain a second measurement value; obtaining a first voltage measurement signal that is dependent on a sum of the first measurement value and the second measurement value; and adjusting the on-time in a successive drive cycle dependent on a feedback signal and the first voltage measurement signal.

A control circuit for controlling an AC-DC power supply, can include: a pulse-width modulation (PWM) signal generating circuit configured to generate a PWM signal in accordance with a reference voltage and a current sampling signal representing an inductor current flowing through an inductor of the AC-DC power supply, and to control a power stage circuit of the AC-DC power supply in accordance with the PWM signal; and a reference voltage generating circuit configured to generate the reference voltage based on an input voltage of the AC-DC power supply.

Provided are electrical circuits and methods for power factor correction. An example method includes receiving, by converter, an input voltage at a fundamental frequency and generating an output voltage; generating, based on the output voltage, a first measurement signal; subtracting a first reference signal from the first measurement signal to obtain a first error signal; generating an adaptive current sense signal, generating a reference voltage based on the input voltage, subtracting the reference voltage from the current sense signal thus generating a second measurement signal to control the current measurement; subtracting the second measurement signal from the input voltage to obtain a difference signal, wherein the difference signal is largely minimized by removing overtones of the fundamental frequency; generating, based on the difference signal, a second error signal; using a sum of the second error signal as a first order correction to the first error signal to regulate the converter.

A conversion apparatus with a three-level switching circuit includes a DC conversion module, a three-level circuit, and a control unit. The three-level circuit includes a bridge arm assembly and a capacitor assembly. The capacitor assembly includes a first capacitor and a second capacitor connected to the first capacitor in series. The DC conversion module has a positive output end and a negative output end, and the positive output end and the negative output end are coupled to the bridge arm assembly. The control unit controls the switching of a second switch unit and a third switch unit to make the three-level circuit operate in a first state where the positive output end and the negative output end are connected to the first capacitor, and operate in a second state where the positive output end and the negative output end are connected to the second capacitor.