Abstract: A radio frequency (RF) generator incorporates an automatic level control (ALC) circuit to control the output level of the RF signal where the ALC circuit implements synchronized ADC sampling, pulse sample indexing, gated accumulation to enable fast ALC loop control, especially for pulse-modulated RF signals. In other embodiments, the ALC circuit implements multi-level control for multi-level RF signals. In this manner, the RF generator uses the ALC circuit to generate an RF signal having a constant power level for RF signals having any pulse shape or output levels. In other embodiments, a clock generation circuit in an impedance matching network synchronizes a slave clock to a clock signal of the RF signal when the load impedance is resistive only or when the clock signal of the RF signal has a given phase condition.

Abstract: A radio frequency (RF) generator incorporates an automatic level control (ALC) circuit to control the output level of the RF signal where the ALC circuit implements synchronized ADC sampling, pulse sample indexing, gated accumulation to enable fast ALC loop control, especially for pulse-modulated RF signals. In other embodiments, the ALC circuit implements multi-level control for multi-level RF signals. In this manner, the RF generator uses the ALC circuit to generate an RF signal having a constant power level for RF signals having any pulse shape or output levels. In other embodiments, a clock generation circuit in an impedance matching network synchronizes a slave clock to a clock signal of the RF signal when the load impedance is resistive only or when the clock signal of the RF signal has a given phase condition.

Abstract: A radio frequency (RF) generator includes a pulse generator circuit configured to receive input signals indicative of a pulse pattern comprising pulse segments, the input signals defining power levels and durations for the pulse segments. The pulse generator circuit generates a pulse modulation control signal for each pulse segment responsive to the input signals. The pulse modulation control signal is coupled to adjust an amplitude and to modulate an RF source signal to generate the pulse RF signal having an envelope defined by the pulse segments of the pulse pattern.

Abstract: A radio frequency (RF) generator includes a pulse generator circuit configured to receive input signals indicative of a pulse pattern defining an envelope of a pulse RF signal. The pulse generator circuit stores data values defining power levels and durations of segments of the pulse pattern. The pulse generator generates a pulse modulation control signal responsive to the stored data values, the pulse modulation control signal being indicative of the power level and the duration of each segment of the pulse pattern, the pulse modulation control signal being provided to a control circuit to generate a control signal to adjust the amplitude and to modulate the duration or width of the RF signal to generate the pulse RF signal having the pulse pattern.

Abstract: A bridgeless interleaved power factor correction (PFC) circuit using a single PFC choke having four windings formed on a single core to form the four input inductors of the PFC circuit. An AC-to-DC converter constructed using the bridgeless interleaved PFC circuit achieves high conversion efficiency with high power factor and low total harmonic distortion. Furthermore, the size of the PFC circuit is reduced by using a single PFC choke with quad-winding.

Abstract: A configurable transformer module includes a primary printed circuit board, one or more secondary printed circuit boards, and one or more interface connectors. The primary PCB has planar primary windings formed thereon and openings for accommodating a planar transformer core. Each of the one or more secondary PCB has planar secondary windings and an opening for accommodating the planar transformer core. Some of the secondary PCB has mating terminals formed thereon. The planar secondary windings on a respective secondary printed circuit board are configured by electrical connections provided at a respective interface connector to realize a given transformer turns ratio between the respective secondary printed circuit board and the primary printed circuit board.

Abstract: An LLC resonant converter implements a primary-side current feedback scheme. The LLC resonant converter includes an isolation transformer having a primary winding and at least one secondary winding and is controlled by a control circuit to operate at a switching frequency. The LLC resonant converter includes a first capacitor connected to the primary winding through AC coupling to sense a first voltage indicative of a current flowing through the primary winding of the isolation transformer, and a current sense circuit configured to receive the first voltage and to generate a feedback signal. The feedback signal is coupled to the control circuit to regulate the switching frequency in response to the current at the primary winding. In another embodiment, the current sense circuit is a current and voltage sense circuit configured to sense a voltage at the primary winding.

Abstract: A bridgeless interleaved power factor correction (PFC) circuit using a single PFC choke having four windings formed on a single core to form the four input inductors of the PFC circuit. An AC-to-DC converter constructed using the bridgeless interleaved PFC circuit achieves high conversion efficiency with high power factor and low total harmonic distortion.