摘要:
A current mode buck-boost converter has an input terminal, an output terminal, and an output capacitor coupled to the output terminal. The input terminal is used to receive an input voltage, and the output terminal is for producing the output voltage. The current mode buck-boost converter comprises a voltage converter and a control circuit. The voltage converter comprises an inductor. The control circuit is for detecting the current passing through the inductor to determine the electric energy transmitted to the output terminal by the voltage converter. Accordingly, the current mode buck-boost converter has fast response, and the electrical energy can be recycled and stored to the voltage source when the current mode buck-boost converter operates in down-tracking process.
摘要:
An adaptive feedback control method of a field sequential color display includes: a rearrangement step of converting gray-scale values of a three primary color field of an input image into gray-scale values of a new three primary color field and a dominated color field; a sampling step of performing a pixel sampling on a resolution of the input image in a sampling interval; a feedback control step of performing a pixel by pixel sum operation for each separated color on a color break-up value and a color value of the input image in a Lu′v′ color space to obtain a color difference sum, and performing a feedback control at a bit precision on the color difference sum; and a liquid crystal/backlight synchronization step of synchronizing a liquid crystal signal and a backlight grayscale value of the input image according to the minimum color difference sum.
摘要:
A power conversion system and power control method for reducing cross regulation effect uses a voltage feedback adjustment circuit to modulate an error signal fed back from an output voltage so as to predict the energy of an output corresponding to its load states. While the energy delivered to an output terminal with its load remaining the same does not change, the energy delivered to an output terminal with its load changing is adjusted accordingly. The power conversion system thus effectively reduces the cross regulation effect and obtains excellent steady system output and transient response.
摘要:
The present invention relates to a current-balance circuit and a backlight module having the same. The current balance circuit includes a current balance unit, a control unit, and a detection unit. The current balance unit is connected to a plurality of light units to regulate the current of the plurality of light units, independent from the effects of input voltage. The detection unit is connected to the plurality of light units and the current balance unit to detect the minimum operating voltage for the plurality of light units. The control unit, connected to the current balance unit, controls the operation of the plurality of light units.
摘要:
A control circuit of a multi-mode buck-boost switching regulator and a method thereof are provided. The control circuit imposes ON/OFF timing sequences on switches according to the relationship between two controlling triangle waves and the load fluctuation. In each working cycle of each mode of the regulator, at most two switches perform switching operations. The control circuit is simple to design, which only includes simple digital elements, such as comparators, logic gates etc., instead of complicated analog circuits.
摘要:
A delay line, an analog-to-digital converting device and a load-sensing circuit using the same are provided. The delay line comprises a delay-control terminal, a reset terminal, n delay cells DCELLx (0
摘要:
A boost DC/DC converter, including a mask circuit, a switched boost circuit, a pulse width modulation (PWM) circuit and an AND gate, is provided. The mask circuit is used to output a mask signal according to a load current. In the present invention, the system can selectively operate in the pulse width modulation mode, the pulse frequency modulation (PFM) mode or the mixed pulse mask mode according to the mask signal corresponding to the load current when the system is under light load, medium load or heavy load respectively, so as to achieve optimal system efficiency.
摘要:
A buck-boost power converter switches the switches thereof with a novel sequence and extends the switching periods of the switches to reduce the switching loss and conduction loss when the input voltage thereof approaches the output voltage thereof. The influence of the load current of the power converter on the duty thereof is taken into account to switch the power converter between modes at correct time points, so as to prevent the output voltage from being affected by the mode switching.
摘要:
A power conversion system and power control method for reducing cross regulation effect uses a voltage feedback adjustment circuit to modulate an error signal fed back from an output voltage so as to predict the energy of an output corresponding to its load states. While the energy delivered to an output terminal with its load remaining the same does not change, the energy delivered to an output terminal with its load changing is adjusted accordingly. The power conversion system thus effectively reduces the cross regulation effect and obtains excellent steady system output and transient response.
摘要:
The present invention is to provide a flyback energy converter comprising a transformer having a primary winding, a secondary winding and an auxiliary winding, a load electrically connected with the secondary winding, a switch serially connected with the primary winding and a primary controlling circuit. The primary controlling circuit comprises a voltage measurement terminal and a switch controlling terminal. The voltage measurement terminal measures an output voltage wave provided from the auxiliary winding to get a part of times in the part of the output voltage wave, so as to enlarge the part of times to a total time. According to a predetermined timing transferred from the total time, the switch controlling terminal controls the switch.