摘要:
The present invention discloses a light emitting device driver chip for driving light emitting devices in series. The chip includes: plural pins electrically connected to corresponding light emitting devices, respectively, wherein an internal voltage is provided through a predetermined one of the pins; a voltage regulation circuit for providing an operation voltage according to the internal voltage; a switch circuit including plural switch groups electrically connected to corresponding pins, respectively; a current source circuit for providing a current to the light emitting devices; and a switch control circuit for controlling the switch groups to determine which light emitting device is turned ON. The light emitting device driver chip does not directly receive the rectified input voltage.
摘要:
The present invention discloses a light emitting device driver circuit. The light emitting device driver circuit drives a light emitting device circuit. The light emitting device circuit includes plural light emitting devices connected in series and a diode circuit, wherein the plural light emitting devices are divided to plural groups. The light emitting device driver circuit includes: a first switch circuit, a second switch circuit, a current source circuit, and a control circuit. The first switch circuit includes plural first switches connected in parallel to the corresponding groups respectively. The second switch circuit includes plural second switches coupled to a forward end and a reverse end of the diode circuit respectively, wherein the second switch circuit determines whether to conduct the forward end or the reverse end to the current source circuit according to the voltages of the forward end and the reverse end.
摘要:
The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
摘要:
The present invention discloses a single-wire transmission method, which includes: providing a transmission signal including alternating high and low levels through a single-wire, wherein a period of one of the high and low levels defining a reference time and a period of the other of the high and low levels defining a content time; determining a relative relationship between the reference time and the content time; when the content time is smaller than a proportion of the reference time, defining the content time to express a first meaning; and when the content time is larger than the proportion of the reference time, defining the content time to express a second meaning.
摘要:
The present invention discloses a power factor correction circuit, a control circuit therefor and a method for driving a power factor correction circuit. The power factor correction circuit receives rectified power obtained by rectifying AC power, and corrects the power factor thereof. The power factor correction circuit includes an inductor, and it generates a reference signal as a limit for the inductor current. The reference signal is proportional to Comp/Vin, wherein Comp is a signal relating to a feedback signal, and Vin is a voltage signal relating to the AC power or the rectified power.
摘要:
An apparatus and method for output voltage calibration of a primary feedback flyback power module extract the difference between the output voltage of the power module and a target value, and according thereto, calibrate a reference voltage which is used in regulation of the output voltage, to thereby calibrate the output voltage to be the target value.
摘要:
An adjustable driver voltage source for a switching power supply uses a linear regulator to provide a driver voltage, and a modulator to adjust the driver voltage according to the loading change of the switching power supply. The modulator may lower the driver voltage at light load to reduce the switching loss and thereby increase the power efficiency of the switching power supply.
摘要:
The present invention discloses a single-wire asynchronous serial interface, and a method for transmitting commands and data through one transmission wire, wherein the transmission wire is capable of transmitting signals of three level states. The disclosed interface comprises a signal level extraction circuit receiving signals transmitted through the wire and outputting logic or functional bits according to the received signals; a clock extraction circuit generating clock signals according to the functional bits, and a memory circuit controlled by the clock signals and storing the logic bits. The disclosed method comprises: using two of the level states to represent logic 0 and logic 1, and the third of the states as a functional bit; and determining whether a group of signals is a command or data by the existence of a functional bit within the group.
摘要:
The present invention discloses a multi-chip module with master-slave analog signal transmission function. The multi-chip module comprises: a master chip having a first setting input pin for receiving an analog setting signal to generate an analog setting in the master chip, and the master chip duplicating the analog setting to output a first analog output; and a first slave chip for receiving the first analog output from the master chip to generate an internal setting of the first slave chip.
摘要:
A mix mode wide range divider is provided for dividing a first signal by a second signal to generate an output signal. A third signal is generated depending on the resistance of a first adjustable resistor, and a fourth signal is generated according to the third signal and a target value determined by the second signal, to adjust the resistance of the first adjustable resistor and the resistance of a second adjustable resistor. The resistance of the first adjustable resistor is so adjusted to make the third signal equal to the target value, and the resistance of the second adjustable resistor is so adjusted to maintain a ratio of the resistance of the second adjustable resistor to the resistance of the first adjustable resistor. The output signal is generated depending on the first signal and the resistance of the second adjustable resistor.