摘要:
The invention provides an analog photovoltaic power circuit with auto zero calibration, which judges whether the current trend or voltage trend has the same direction as or different direction from the power trend, and adjusts an input/output power conversion accordingly, so that an input current approaches to an optimum current corresponding to a maximum power point, in which the judgments of the current trend, voltage trend and power trend is calibrated with auto-zero circuitry.
摘要:
The present invention discloses a backlight control circuit with flexible configuration, comprising: a light emitting device path; a current source for controlling the current amount on the light emitting device path, the current source receiving a relatively high reference voltage in a first state, and receiving a relatively low reference voltage in a second state; and a current source control circuit for controlling the current source, whereby when the light emitting device path is in normal use, the current source is set to the first state, and when the light emitting device path is not in normal use, the current source is set to the second state.
摘要:
The present invention discloses a current splitter circuit for splitting a supply current to multiple light emitting device strings of a light emitting device array. The current splitter circuit includes: a minimum selector circuit coupled to the multiple light emitting device strings to generate a minimum signal which indicates a minimum voltage of the light emitting device strings; and multiple current source circuits each including a first current source end coupled to a corresponding light emitting device string, a second current source end coupled to ground, and a current source control end receiving a current control signal related to the minimum signal, so as to control currents through the corresponding light emitting device string.
摘要:
The present invention discloses an analog photovoltaic power circuit, including: a photovoltaic device group for receiving photo energy to generate an input voltage, the input voltage corresponding to an input current; a power stage circuit for receiving the input voltage and generating an output voltage; an optimum current or voltage estimation circuit for receiving a predetermined voltage and estimating an optimum current or voltage point corresponding to an optimal output point according to a direction of variation of the input current and a direction of variation of the power generated by the photovoltaic device group; and an analog comparison and control circuit for comparing the optimum current or voltage with the input current or voltage, to thereby control the operation of the power stage circuit.
摘要:
A power converter includes a first conversion stage for converting an input voltage to a first output voltage and a second conversion stage for converting the first output voltage to a second output voltage. An error signal is generated according to a reference voltage and a feedback signal extracted from the second conversion stage, and a feed forward signal is generated from the error signal and injected into the first conversion stage to stabilize the first output voltage. The feedback signal is a function of the second output voltage and thus, the error signal varies with the second output voltage. As a result, the first output voltage will be stabilized when the second output voltage varies, due to the varied feed forward signal.
摘要:
The present invention discloses a light emitting device control method for adjusting the brightness of the light emitting device by an AC signal, comprising: receiving a signal having a turn ON angle and converting the signal to a DC signal; obtaining an average of the DC signal level, the average being a function of the turn ON angle; determining a reference voltage of a current source circuit according to the average of the DC signal level; and controlling a current flow through the light emitting device by the current source circuit.
摘要:
The present invention discloses a backlight control circuit, comprising: a voltage supply circuit, under control by a control signal, for receiving an input voltage and generating an output voltage; a plurality of nodes for respectively indicating the current status of corresponding light emission device paths; and a high-low voltage comparison and amplifier circuit for generating the control signal according to a voltage difference between at least two nodes.
摘要:
The present invention discloses an active bleeder circuit capable of triggering a tri-electrode AC switch (TRIAC) circuit in all phase. The active bleeder circuit receives a rectified signal having an OFF phase and an ON phase. The active bleeder includes: a detection circuit for generating a detection signal according to the rectified signal and accumulating the detection signal in the OFF phase of the rectified signal; and a current sinker circuit coupled to the detection circuit, for generates a latching current to trigger the TRIAC circuit by operating a switch when the detection signal exceeds a predetermined level. The present invention also discloses a light emitting device power supply circuit and a TRIAC control method using the active bleeder circuit.
摘要:
The present invention discloses a multi-color light emitting device circuit, which includes: multiple light emitting device strings of different colors, a timing control circuit, a power regulator circuit, and preferably a dark feedback circuit. Each light emitting device string has multiple light emitting devices coupled in series. The number of the light emitting devices of each light emitting device string is determined by an operational voltage of the light emitting device, wherein at least two of the light emitting device strings have different numbers of the light emitting devices, such that voltage drops of the two light emitting device strings are closer to each other than in a case wherein the two light emitting device strings have the same number of the light emitting devices, and the response time of the light emitting device strings are increased.
摘要:
The present invention discloses a light emitting device driver circuit and a method for driving a light emitting device. In the present invention, the secondary windings of a transformer provide positive and negative secondary voltages, so as to generate positive and negative output voltages. A light emitting device circuit is coupled between the positive and negative output voltages. As such, the specification to withstand high voltage for a device in the circuit is reduced.