Abstract: The present disclosure provides an alternating current (AC)/direct current (DC) voltage detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When the operating voltage is higher than the preset voltage, the determination circuit activates the detection and output circuit to detect the change of the operating voltage and the target flip.

Abstract: The present disclosure provides an alternating current (AC)/direct current (DC) voltage detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When the detection and output circuit detects that the output signal of the rising edge trigger circuit undergoes preset m target flips in M consecutive clock periods, the detection and output circuit generates an AC determination signal, where m is a natural number.

Abstract: The present disclosure provides an alternating current (AC)/direct current (DC) voltage detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When an increase of the operating voltage at the rising edge of the operating voltage in one clock period is greater than the magnitude of a preset bias voltage, an output signal of the output terminal undergoes at least one target flip between a high level and a low level. When a detection result shows that the output signal of the rising edge trigger circuit undergoes preset m (a natural number) target flips in preset M consecutive clock periods, the detection and output circuit generates an AC determination signal.

Abstract: The present disclosure provides a voltage fluctuation detection circuit, which includes a voltage adjustment circuit and a comparator. The voltage adjustment circuit includes an adjustment circuit input terminal to receive the operating voltage, a first adjustment circuit output terminal to output a first voltage, and a second adjustment circuit output terminal to output a second voltage that is step-shaped, the second voltage differs from the first voltage by a bias voltage at the beginning of a preset clock period and falls within a first amplitude within the preset clock period, the magnitude of the bias voltage is related to the first voltage. The comparator includes: a first comparator input terminal to receive the first voltage, a second comparator input terminal to receive the second voltage, and a comparator output terminal to output a comparison result of the first voltage and the second voltage.

Abstract: The present disclosure provides a voltage fluctuation detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When a change of the operating voltage within a preset clock period is greater than a preset bias voltage, an output signal of the output terminal undergoes at least one target flip between a high level and a low level. When the output signal of the rising edge trigger circuit always undergoes the target flips in N consecutive preset clock periods, and the operating voltage is always not less than a starting threshold value in each target flip of all the target flips in the N consecutive clock periods, the detection and output circuit generates an first signal, where N is a natural number not less than 2.

Abstract: The present disclosure provides a voltage fluctuation detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When a change of the operating voltage within a preset clock period is greater than a preset bias voltage, an output signal of the output terminal undergoes at least one target flip between a high level and a low level. When the output signal of the rising edge trigger circuit always undergoes the target flips in N consecutive preset clock periods, and the operating voltage is always not less than a starting threshold value in each target flip of all the target flips in the N consecutive clock periods, the detection and output circuit generates an first signal, where N is a natural number not less than 2.

Abstract: The present disclosure provides an alternating current (AC)/direct current (DC) voltage detection circuit, which includes a rising edge trigger circuit and a detection and output circuit connected to an output terminal of the rising edge trigger circuit. When an increase of the operating voltage at the rising edge of the operating voltage in one clock period is greater than the magnitude of a preset bias voltage, an output signal of the output terminal undergoes at least one target flip between a high level and a low level. When a detection result shows that the output signal of the rising edge trigger circuit undergoes preset m (a natural number) target flips in preset M consecutive clock periods, the detection and output circuit generates an AC determination signal.

Abstract: The present disclosure provides a voltage fluctuation detection circuit, which includes a voltage adjustment circuit and a comparator. The voltage adjustment circuit includes an adjustment circuit input terminal to receive the operating voltage, a first adjustment circuit output terminal to output a first voltage, and a second adjustment circuit output terminal to output a second voltage that is step-shaped, the second voltage differs from the first voltage by a bias voltage at the beginning of a preset clock period and falls within a first amplitude within the preset clock period, the magnitude of the bias voltage is related to the first voltage. The comparator includes: a first comparator input terminal to receive the first voltage, a second comparator input terminal to receive the second voltage, and a comparator output terminal to output a comparison result of the first voltage and the second voltage.

Abstract: The disclosure provides a charging device, which includes an input terminal configured to receive an input voltage; an output terminal configured to connect a target load so as to charge the target load; a control terminal, configured to receive a control voltage; a junction field-effect transistor and a control circuit. The junction field-effect transistor includes at least: a drain, electrically connected to the input terminal so as to receive the input voltage; a source, electrically connected to the output terminal so as to output an output voltage and an output current; and a gate, electrically connected to the control terminal. The control circuit is electrically connected to the control terminal, and configured to change the control voltage based on a change in a load voltage so as to change a pinch-off voltage of the JFET by controlling a bias voltage on the gate, thereby controlling the output current.

Abstract: A frequency controller for operating a switching power converter is provided. The frequency controller includes an output circuit, an operation signal generator, and a transition signal generator. The output circuit is to connect to a switching power converter. The startup signal generator is connected to the output circuit via a first connection line and configured to generate a startup signal with a startup-frequency during a startup period of the switching power converter. The operation signal generator is connected to the output circuit via a second connection line and configured to generate an operation signal with an operation-frequency during an operation period of the switching power converter. The transition signal generator is connected to the output circuit via a third connection line and configured to generate a transition signal with varied frequencies during a transition period between the startup period and the operation period.