摘要:
A circuit includes a timer circuit configured to generate a first control signal defining a first time period and a second control signal defining a second time period. A controller is configured to control a high-side and a low-side transistor of a half-bridge circuit in response to the first and second control signals only during a first switching cycle of the half-bridge circuit. The half-bridge circuit includes a bootstrap capacitor coupled to a node between the high-side and low-side transistors. The controller turns on the low-side transistor for the first time period during the first switching cycle and configured turns off the low-side and the high-side transistors for the second time period during the first switching cycle.
摘要:
A method of operating an electronic converter is provided in which a switching activity of a switching stage of the electronic converter is active or inactive based on a control signal, and the method includes operating the electronic converter, alternatively, in a first or a second mode. In the first mode, the status signal is initially asserted and is de-asserted in response to an amplitude of the input sensing signal failing to reach a first reference threshold value. In the second mode, the status signal is initially de-asserted and an auxiliary power supply signal is periodically varied with a variation period. After a time interval equal to the variation period, a comparison signal is asserted in response to an amplitude of the sensed signal reaching a second reference threshold value. The status signal is asserted based on conditions of the comparison signal and the periodically varying auxiliary power supply signal.
摘要:
A control device controls a switching circuit for a converter. The switching circuit comprises a half-bridge having a high-side transistor and a low-side transistor. The control device comprises a controller configured to control turning on and turning off said two transistors, so that a square-wave voltage is applied to the transformer primary. The controller is configured to start switching the half-bridge by turning on the low-side transistor. The control device comprises a first timer configure to initially turn on the low-side transistor for a duration given by a first time period useful for pre-charging a bootstrap capacitor couplable to the middle point of the half-bridge, and a second timer configured to keep the low-side transistor and the high-side transistor turned off for a second time period immediately following the first time period and having a longer duration than the first time period.
摘要:
A control device of a switching circuit of a resonant apparatus is described. The switching circuit comprises at least one half-bridge having a high-side transistor and a low-side transistor connected between an input voltage and a reference voltage; the resonant apparatus comprises a resonant load. The control device is configured to determine the on time period and the off time period of the transistors alternatively and a dead time of both the transistors so that a periodic square-wave voltage is applied to the resonant load. The control device comprises a detector adapted to detect the current sign flowing through the resonant load and a correction circuit configured to extend the current operating time period of said two transistors in response to at least the current sign detected from the detection means.
摘要:
A control circuit for controlling a switching stage of an electronic converter includes a first terminal configured to provide a drive signal and a second terminal configured to receive a first feedback signal. A third terminal receives a second feedback signal and a driver circuit provides the drive signal as a function of a PWM signal. A PWM signal generator circuit generates the PWM signal as a function of the first feedback signal, a reference threshold and the second feedback signal or a slope compensation signal. The control circuit is configured to sense an input signal, provide a first compensation parameter, and provide a first compensating signal as a function of a power of the input sensing signal.
摘要:
A control device controls a switching circuit for a converter. The switching circuit comprises a half-bridge having a high-side transistor and a low-side transistor. The control device comprises a controller configured to control turning on and turning off said two transistors, so that a square-wave voltage is applied to the transformer primary. The controller is configured to start switching the half-bridge by turning on the low-side transistor. The control device comprises a first timer configure to initially turn on the low-side transistor for a duration given by a first time period useful for pre-charging a bootstrap capacitor couplable to the middle point of the half-bridge, and a second timer configured to keep the low-side transistor and the high-side transistor turned off for a second time period immediately following the first time period and having a longer duration than the first time period.
摘要:
A control device of a switching circuit of a resonant apparatus is described. The switching circuit comprises at least one half-bridge having a high-side transistor and a low-side transistor connected between an input voltage and a reference voltage; the resonant apparatus comprises a resonant load. The control device is configured to determine the on time period and the off time period of the transistors alternatively and a dead time of both the transistors so that a periodic square-wave voltage is applied to the resonant load. The control device comprises a detector adapted to detect the current sign flowing through the resonant load and a correction circuit configured to extend the current operating time period of said two transistors in response to at least the current sign detected from the detection means.
摘要:
A circuit includes a timer circuit configured to generate a first control signal defining a first time period and a second control signal defining a second time period. A controller is configured to control a high-side and a low-side transistor of a half-bridge circuit in response to the first and second control signals only during a first switching cycle of the half-bridge circuit. The half-bridge circuit includes a bootstrap capacitor coupled to a node between the high-side and low-side transistors. The controller turns on the low-side transistor for the first time period during the first switching cycle and configured turns off the low-side and the high-side transistors for the second time period during the first switching cycle.