摘要:
The present invention discloses a driver circuit and a method for driving a load circuit. The driver circuit includes: a primary side circuit receiving rectified AC power; a transformer coupled to the primary side circuit and converting a primary voltage to a secondary voltage which is supplied to a load circuit; and a secondary side circuit coupled to the transformer, the secondary side circuit detecting current flowing through the load circuit and feedback controlling the primary side circuit accordingly.
摘要:
The present invention discloses a synchronous driver circuit, comprising: an inductor having one end coupled to an input voltage; a first power transistor having one end coupled to the other end of the inductor and another end supplying an output voltage; a second power transistor having one end coupled to the other end of the inductor and another end coupled to ground; a control circuit for controlling the operation of the first and second power transistors; a gate driver coupled to the control circuit and having an output controlling the gate of the first power transistor; and a bootstrap capacitor having one end coupled to a voltage node and the other end coupled to the other end of the inductor, the voltage across the bootstrap capacitor being provided as the operational voltage of the gate driver.
摘要:
The present invention discloses an AC power line controlled light emitting device dimming circuit and a method thereof. The AC power line controlled light emitting device dimming circuit includes: a light emitting device driver circuit for controlling current through a light emitting device, wherein the light emitting device is current-controlled; and a level adjustment circuit for detecting power-OFF of an AC power switch and generating a corresponding level adjustment signal which is transmitted to the light emitting device driver circuit to control the current through the light emitting device accordingly.
摘要:
The present invention discloses a tail-less LED control circuit, which includes: a power supply stage having an output terminal which provides electrical power to an LED circuit; an output capacitor coupled to the output terminal; an LED driver circuit coupled to the power supply stage for controlling the power supply stage to provide the electrical power to the LED circuit, the LED driver circuit receiving a PWM dimming signal for adjusting brightness of the LED circuit; and a MOSFET switch coupled to the output capacitor in series, the MOSFET switch switching synchronously with the PWM dimming signal to alleviate LED afterglow, wherein the MOSFET switch includes a body diode having an anode-cathode direction against the discharge direction of the output capacitor.
摘要:
The present invention discloses a light emitting device array controller which controls a power stage to supply an output voltage to one end of each of a plurality of light emitting device strings. The other end of each of the light emitting device strings is coupled to a corresponding transistor having a current inflow end, a current outflow end and a control end. The present invention obtains signals from the control ends of the transistors instead of the current inflow ends, and feedback controls the output voltage according to the highest voltage of the control ends. Thus, the number of pins required for a circuit chip is reduced.
摘要:
The present invention discloses a short circuit protection circuit comprising: a first input terminal; a second input terminal; an output terminal; at least two transistors including a first and a second transistors connected in series with each other and electrically connected between the first input terminal and the output terminal; and a voltage source circuit electrically connected with the first input terminal, the second input terminal, the output terminal, and the gates of the first and second transistors.
摘要:
The present invention discloses a current-matching method comprising steps of: providing a plurality of current channels; grouping the plurality of current channels into W sets, each of which has Q channels; and matching the channels of the same set in current, where both W and Q are integers greater than or equal to 2.
摘要:
The present invention discloses a backlight control circuit, comprising: a voltage supply circuit, which is a boost converter circuit for receiving an input voltage from an input terminal and generating an output voltage to an output terminal, the output voltage being provided as an operating voltage for a plurality of light emitting devices; at least one input capacitor electrically connected between the input terminal and ground; and at least one output capacitor electrically connected between the output terminal and the input terminal.
摘要:
The present invention discloses a multi-color backlight control circuit, comprising: a plurality of pins for electrically connecting with a plurality of LED strings of different LED colors; and a voltage supply circuit for receiving an input voltage and supplying a single output voltage to the plurality of LED strings of different LED colors. The present invention also discloses a multi-color backlight control method, comprising: supplying a single output voltage to a plurality of LED strings of different LED colors.
摘要:
A two-step spacer etch is used for the formation of a spacer in CMOS fabrication. A dry etch is first applied to remove part of the spacer material on the silicon substrate and leave a thin layer of the spacer material remained on the silicon substrate. Then, a wet etch is applied to completely remove the thin layer of the spacer material on the silicon substrate. The wet etch has good etch selectivity between the spacer material and silicon, and thus will not damage the surface of the silicon substrate when the spacer is formed. Therefore, the BJT on the silicon substrate is prevented from junction leakage.