摘要:
A light emitting diode (LED) driving system comprises a plurality of current limitation circuits and a plurality of over-voltage protection circuits to driving a plurality of LED strings. Each of the current limitation circuits comprises a first switch comprising a control pole receiving a reference voltage, a first pole correspondingly connected to a LED string, and a second pole connected to the ground via a first resistor and a second switch comprising a control pole connected to the second pole of the first switch via a second resistor, a first pole receiving the reference voltage, and a second pole grounded. Each of the over-voltage protection circuits comprises a zener diode, a third switch and a first capacitor.
摘要:
A solar power supply system includes at least one solar power conversion circuit and an inverter circuit. Each solar power conversion circuit comprises a solar module and a direct current (DC) module. The solar module converts the solar power into the DC signals. The DC module with two-stage conversion comprises a DC transformer circuit and a maximum power point tracking circuit, to boost the DC signals and adjust output power of the solar module to a maximum value. The inverter circuit converts the boosted DC signals output from the solar power conversion circuits into AC signals and combines the AC signals into the AC utility network.
摘要:
An ionic thermal dissipation device includes an ionic wind generation system and a power system. The power system first converts external direct current (DC) power signals into first alternating current (AC) power signals, and boosts, increases voltage, and rectifies the first AC power signals to generate high voltage DC power signals to drive the ionic wind generation system. The power system also detects current signals generated by ion excitation of the ionic wind generation system and voltage signals of the high voltage DC power signals, and regulates the high voltage DC power signals and time of driving the ionic wind generation system according to a first PWM signal and a first analog signal from an electronic device and the detected current signals and voltage signals.
摘要:
A backlight module positioned on a printed circuit board (PCB) includes a power control circuit, a transformer, and a voltage detection component. The power control circuit outputs power signals. The transformer has a primary winding and at least one secondary winding. The primary winding is connected to the power control circuit and receives the power signals. The voltage detection component is positioned on a high voltage terminal of the secondary winding of the transformer, detecting voltage variations in the high voltage terminal of the secondary winding of the transformer, and outputting the detected voltage variation to the power control circuit. The power control circuit adjusts the output power signals according to the detected voltage variation.
摘要:
A system for driving a lamp module (13) includes a converter (11), a driving circuit (12), and a pulse width modulation (PWM) controller (14). The lamp module includes a plurality of lamps. The converter converts a received voltage to a direct current (DC) voltage. The driving circuit converts the DC voltage to an alternating current (AC) voltage. The PWM controller is connected between the converter and the lamp module, for regulating the DC voltages outputted from the converter according to current flowing through the lamps of the lamp module. In one embodiment, the system includes a bus inverter controller. The bus inverter controller is connected between the driving circuit and the lamp module, for regulating a working frequency thereof and controlling the AC voltage outputted from the driving circuit when the lamps are turned on. The system has a reduced number of PWM controllers and a relatively low cost.
摘要:
An ion airflow generating device includes a number of generator stages, each of which includes a number of generators. Each generator includes a needle-shaped emitter and a ring-shaped receiver. The receivers in the same stage are arranged in an array. Each receiver defines a groove in an outer circumferential surface thereof along a direction parallel to the central axis thereof. Each two adjacent receivers in a former generator stage connect with each other, and the grooves thereof cooperatively define a hole for holding an emitter in a next generator stage. The receivers in the next generator stage symmetrically offset from the receivers in the former generator stage such that each emitter aligns to the center of a corresponding receiver.
摘要:
A discharge lamp driving device includes a power stage circuit, a transformer circuit, a control circuit, a feedback circuit and a lamp protection circuit. The lamp protection circuit includes a current sensing circuit, a reference voltage selecting circuit, a comparing circuit and a protection signal generating circuit. The current sensing circuit senses current signals flowing through the lamps, and transforms the current signals to voltage signals. The reference voltage selecting circuit is connected to the current sensing circuit. The comparing circuit is connected to the current sensing circuit and the comparing circuit. The protection signal generating circuit is connected between the comparing circuit and the control circuit. The control circuit is connected to the comparing circuit.
摘要:
A multi-lamp driving system includes a power stage circuit, a pulse width modulation (PWM) controller, a plurality of transformer circuits, and an abnormal detection circuit. Each of the transformer circuits includes a first primary winding and a second primary winding connected in series and a first secondary winding and a second secondary winding respectively outputting AC power signals to drive at least one lamp. The abnormal detection circuit is connected to a junction of the first primary winding and the second primary winding of each of the transformer circuits, and determines if voltages of the junction of the first primary winding and the second primary winding of each of the transformer circuits are different to determine if the at least two lamps are normal. The abnormal detection circuit further generate control signals to control the PWM controller upon the condition that one of the at least two lamps are abnormal.
摘要:
An ionic thermal dissipation device includes an ionic wind generation system and a power system. The power system first converts external direct current (DC) power signals into first alternating current (AC) power signals, and boosts, increases voltage, and rectifies the first AC power signals to generate high voltage DC power signals to drive the ionic wind generation system. The power system also detects current signals generated by ion excitation of the ionic wind generation system and voltage signals of the high voltage DC power signals, and regulates the high voltage DC power signals and time of driving the ionic wind generation system according to a first PWM signal and a first analog signal from an electronic device and the detected current signals and voltage signals.
摘要:
A discharge lamp driving device includes a power stage circuit, a transformer circuit, a control circuit, a feedback circuit and a lamp protection circuit. The lamp protection circuit includes a current sensing circuit, a reference voltage selecting circuit, a comparing circuit and a protection signal generating circuit. The current sensing circuit senses current signals flowing through the lamps, and transforms the current signals to voltage signals. The reference voltage selecting circuit is connected to the current sensing circuit. The comparing circuit is connected to the current sensing circuit and the comparing circuit. The protection signal generating circuit is connected between the comparing circuit and the control circuit. The control circuit is connected to the comparing circuit.