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 voltage converter for use in a backlight module stores energy of an input voltage using an inductor and outputs a plurality of output voltages accordingly. The charging path of the inductor is controlled according to the first output voltage so that the first output voltage can be stabilized. The discharging paths from the inductor to other output voltages are controlled according to the differences between other output voltages and the first output voltage so that other output voltages can also be stabilized.
摘要:
A voltage converter for use in a backlight module stores energy of an input voltage using an inductor and outputs a plurality of output voltages accordingly. The charging path of the inductor is controlled according to the first output voltage so that the first output voltage can be stabilized. The discharging paths from the inductor to other output voltages are controlled according to the differences between other output voltages and the first output voltage so that other output voltages can also be stabilized.
摘要:
A power supply device is disclosed in the present invention, which includes a DC-DC boost converter and a charge recycling circuit. The DC-DC boost converter is utilized for boosting an input voltage to generate an output voltage, and adjusting a voltage level of the output voltage according to a level switching signal. The charge recycling circuit is electrically connected to the DC-DC boost converter, and is utilized for generating a current path according to the level switching signal to recycle redundant charges from the DC-DC boost converter when the output voltage is switched from high to low and to return stored charges back to the DC-DC boost converter when the output voltage is switched from low to high, so as to accelerate voltage switching of the output voltage and to reduce power consumption of the DC-DC boost converter.
摘要:
A driving circuit of a backlight module is provided. The driving circuit has a dimming unit used for transmitting signals, wherein the dimming unit can adjust a current flowing through a light-emitting diode (LED) according a pulse width modulation signal and an enable signal, so as to adjust a light-emitting intensity of the LED. In the present invention, fewer devices are used to implement the dimming unit, and a transmission gate is replaced by a N-type transistor and a P-type transistor, such that a chip area and a circuit cost of the driving circuit are reduced.
摘要:
In a capacitance sensing analog circuit of a touch panel sensing circuit, by raising a magnitude of a current flowing through a sensing capacitor to form an amplified sensing capacitance, while sensing the amplified sensing capacitance with the aid of pulse width modulation signals, higher resolution of the original sensing capacitance may thus be achieved. Besides, by using a self-calibrating capacitance sensing circuit on the touch panel sensing circuit, linear errors and DC errors of an output signal of the capacitance sensing analog circuit may be filtered off, and thereby resolution of a capacitance amplifying ratio may be effectively raised so as to relieve errors within the capacitance amplifying ratio caused by noises.
摘要:
A capacitance sensing circuit for a touch panel includes an analog capacitance-detecting circuit, a PWM-to-digital circuit and a self-calibration circuit. The analog capacitance-detecting circuit detects the capacitance of the touch panel based on a charging current, and converts the detected capacitance into a PWM control signal. The PWM-to-digital circuit converts the PWM control signal into a sensing count value based on a clock signal. The self-calibration circuit adjusts the value of the charging current or the frequency of the clock signal according to the difference between the range of the sensing count value and a predetermined detecting range. The predetermined detecting range can thus be adjusted for matching the range of the sensing count value.
摘要:
A backlight module control system includes a plurality of backlight sub-modules, a control signals output unit, a voltage converter and a plurality of current control units. The control signals output circuit is for providing a voltage control signal, a current control signal and a plurality of PWM signals; the voltage converter is coupled to the control signals output circuit and the backlight sub-modules, and is for outputting an output voltage to the backlight sub-modules according to the voltage control signal; the current control units are coupled to the backlight sub-modules, respectively, and each current control unit is for determining a current of its corresponding backlight sub-module according to the current control signal, and each current control unit is further utilized for determining whether its corresponding backlight sub-module is enabled or not according to its corresponding PWM signal. In addition, only one backlight module is enabled at a same time.
摘要:
A driving circuit of a backlight module is provided. The driving circuit has a dimming unit used for transmitting signals, wherein the dimming unit can adjust a current flowing through a light-emitting diode (LED) according a pulse width modulation signal and an enable signal, so as to adjust a light-emitting intensity of the LED. In the present invention, fewer devices are used to implement the dimming unit, and a transmission gate is replaced by a N-type transistor and a P-type transistor, such that a chip area and a circuit cost of the driving circuit are reduced.
摘要:
A capacitance sensing circuit for a touch panel includes an analog capacitance-detecting circuit, a PWM-to-digital circuit and a self-calibration circuit. The analog capacitance-detecting circuit detects the capacitance of the touch panel based on a charging current, and converts the detected capacitance into a PWM control signal. The PWM-to-digital circuit converts the PWM control signal into a sensing count value based on a clock signal. The self-calibration circuit adjusts the value of the charging current or the frequency of the clock signal according to the difference between the range of the sensing count value and a predetermined detecting range. The predetermined detecting range can thus be adjusted for matching the range of the sensing count value.