Abstract: An operational amplifier includes an output unit, a voltage drop element and a feedback unit. The output unit is provided for sourcing an output current to an output of the operational amplifier when operating with a power unit for providing a current being multiple times the value of the output current. The voltage drop is provided for generating a voltage drop in accordance with the output current. The feedback unit is controlled with the voltage drop generated by the voltage drop element and controls the output unit and the power unit to regulate the output current in accordance with the voltage drop.

Abstract: A level shift circuit includes an inverter, a shifting circuit, a first transistor, and a second transistor. The inverter inverts an original input signal into an inverted input signal. The shifting circuit generates a control signal according to the original input signal, the inverted input signal, and a reference voltage. The first transistor has a gate, a source, and a drain, in which the gate of the first transistor receives the control signal, and the source of the first transistor is connected to a high supply voltage. The second transistor has a gate, a source, and a drain, in which the gate of the second transistor receives the inverted input signal, the drain of the second transistor is connected to the drain of the first transistor, and the source of the second transistor is connected to a ground terminal or a low supply voltage.

Abstract: An LED driver circuit and its control circuit for controlling its power switch are provided. The LED driver includes a switch, a PWM controller, a current source and a signal controller. The switch has a first end outputting a driving voltage to at least one LED. The PWM controller provides a PWM signal. The current source provides a driving current flowing through the LED when a dimming control signal is asserted. The signal controller turns off the switch when the dimming control signal is de-asserted and relays the PWM signal from the PWM controller to the switch so that the switch is controlled by the PWM signal when the dimming control signal is asserted.

Abstract: A light-emitting diode driving circuit includes a control circuit, a transistor switch and a compensating circuit. The control circuit receives an oscillating signal to generate a pulse drive signal. The transistor switch is activated by the pulse drive signal such that an inductor is charged by an input voltage, in which the inductor is arranged to deliver an inducting current to at least one light-emitting diode when the transistor switch is deactivated. The compensating circuit is coupled between the control circuit and a capacitor provided for reducing ripples of an output voltage corresponding to the inducting current. The compensating circuit performs a charging and discharging operation along with the capacitor when controlled by a dimming control signal provided to control brightness of the light-emitting diode.

Abstract: An audio power amplifier includes a pre-amplifier, an error amplifier, a comparator, a bridge circuit, and a feedback circuit, in which the gain of the pre-amplifier gradually increases when the audio power amplifier is powered on. The comparator generates a PWM signal by comparing a reference signal and an amplified audio signal. The bridge circuit has switches controlled according to the PWM signal such that a driving current alternately flows to and from a load. The feedback circuit generates the feedback signal indicating a condition of the load.

Abstract: An audio power amplifier package includes a non-signal lead, a first non-signal pad, a second non-signal pad and a plurality of bonding wires. The first non-signal pad and the second non-signal pad are disposed on a substrate. The bonding wires connect the non-signal lead to the first non-signal pad and the second non-signal pad respectively.

Abstract: A power amplifier with noise shaping is disclosed. The power amplifier with noise shaping is able to minimize the noise interference a regular power amplifier encounters. The power amplifier includes a differential-mode integrator, a driving unit, and a low pass filter and integration unit. The differential-mode integrator receives a differential-mode input signal and a differential-mode feedback signal and performs integration operations to output a differential-mode intermediate signal. The driving unit outputs a differential-mode output signal and drives a load according to the differential-mode intermediate signal. The low pass filter and integration unit performs a filtering operation on the differential-mode output signal and integration operations to output the differential-mode feedback signal to the differential-mode integrator.

Abstract: A voltage converter to convert a high voltage to a low voltage is provided. The voltage converter comprises: a current mirror, a current bias, a plurality of loads and a low voltage output. The current mirror comprises a first PMOS and a second PMOS, wherein the source of the first PMOS and the second PMOS receive a high voltage input which is a supply voltage of the current mirror, and the gate of the first PMOS is connected to the drain of the first PMOS. The current bias is connected between the drain of the first PMOS and a ground potential. The plurality of loads are parallel connected between the drain of the second PMOS and the ground potential. And the low voltage output connected to the drain of the second PMOS.

Abstract: A current sense circuit includes a power transistor, a first level shifter, an operational transconductance amplifier (OTA), a second level shifter, and a dummy transistor. The power transistor has a first terminal and a power control terminal coupled to a control voltage. The first level shifter is coupled to the first terminal and pulls up a voltage of the first terminal to an operating voltage. The OTA is coupled to the first level shifter and converts the operating voltage into an operating current. The second level shifter is coupled to the OTA and pulls down the operating voltage to the voltage of the first terminal. The dummy transistor has a dummy control terminal with the control voltage, and a third terminal coupled to the second level shifter and having the same voltage as the voltage of the first terminal.

Abstract: A slope compensation circuit includes a first differential pair circuit, a current mirror unit, a first operating current generation circuit, and a transconductance compensation circuit. The first differential pair circuit is connected to a first current source and receives a pair of differential oscillation signals to generate a pair of differential currents corresponding to the differential oscillation signals. The current mirror unit is connected to the first differential pair circuit and mirrors the differential currents. The first operating current generation circuit is connected to the current mirror unit and generates a first operating current including the differential currents. The transconductance compensation circuit stabilizes a quiescent operating point of the first operating current generation circuit and receives the differential oscillation signals to generate an output current multiple times the value of the first operating current.

Abstract: A short detection circuit to detect a short condition in a backlight module, wherein the backlight module comprises a WLED circuit having a first terminal connected to an output voltage and second terminal connected to a driver IC. The short detection circuit comprises: a PMOS, a NMOS, a load and a detection module. The gate of the PMOS receives a first voltage and the source of the PMOS connects to the second terminal; the gate of the NMOS receives a reference voltage, the drain of the NMOS connects to the drain of the PMOS and the source of the NMOS connects to a detection terminal. The voltage of the detection terminal becomes a high state when the WLEDs have a short condition; and the detection module is connected to the detection terminal, when the voltage of the detection terminal becomes a high state, the detection module detects a short condition.

Abstract: A class D audio amplifier includes an error amplifier, a comparator, a bridge circuit, a feedback circuit and a silent start circuit. The error amplifier generates an error signal by amplifying a difference between a feedback signal and an audio input signal. The comparator generates a first pulse width modulation (PWM) signal by comparing a first triangular-wave signal and the error signal. The bridge circuit has switches alternately conducting a current flowing into and from a load. The feedback circuit generates the feedback signal indicating a condition of the load. The silent start circuit performs AND operation of the first PWM signal and a second PWM signal having a gradually increased duty ratio to generate a third PWM signal for control of the switches of the bridge circuit.

Abstract: A driving circuit to drive an output stage comprising a high side NMOS and a low side NMOS is provided. The driving circuit comprises: a diode comprising an anode and a cathode, wherein the anode is electrically connected to a first voltage source and the sources of a first and a second PMOS; a third and a fourth PMOS both comprising a drain, a source and a gate, wherein the sources are respectively connected to the gates of the second and first PMOS, the drains are respectively connected to the drains of the first and second PMOS. A first and a second NMOS both comprise a drain, a source and a gate, wherein the drains are respectively connected to the drain of the fourth and third PMOS, the sources are coupled to a second voltage source, the gates are respectively connected to a first input and a second input.

Abstract: A semiconductor device includes a first metal region, a plurality of vias, a plurality of second metal regions, a plurality of openings and a third metal region. The first metal region conducts source/drain current. The second metal regions are electrically connected to the first metal region through the vias for conducting the source/drain current, in which each of the second metal regions is disposed in a distance from the adjacent second metal regions. The third metal region is electrically connected to the second metal regions through the openings, in which the resistance of the third metal region is smaller than the resistances of the first metal region and the second metal regions.

Abstract: A semiconductor device has a plurality of drain metal blocks, a plurality of source metal blocks, a plurality of polysilicon strips, a first source metal strip, a first drain metal strip, and a plurality of first conductive wires. Each of the source metal blocks is disposed between two of the drain metal blocks, and at least two of the polysilicon strips are correspondingly disposed across one of the drain metal blocks and one of the source metal blocks. The first source metal strip, in the absence of the polysilicon strips, is electrically connected to some of the source metal blocks. The first drain metal strip, in the absence of the polysilicon strips, is electrically connected to some of the drain metal blocks. The first conductive wires, coupled to the polysilicon strips, form a plurality of grids.

Abstract: A driving circuit includes a DC-to-DC voltage converter, a current source, a detector and a feedback control circuit. The DC-to-DC voltage converter has a switch and generates a driving voltage on first ends of the series of light emitting diodes, in which a magnitude of the driving voltage is correlated with conduction of the switch. The current source is coupled to second ends of the series of the light emitting diodes and provides driving currents flowing through the light emitting diodes. The detector generates a feedback voltage corresponding to a sum of voltages on the second ends of the series of the light emitting diodes. The feedback control circuit generates a first control signal which controls the conduction of the switch in response to the feedback voltage.

Abstract: An LED driver circuit and its control circuit for controlling its power switch are provided. The LED driver includes a switch, a PWM controller, a current source and a signal controller. The switch has a first end outputting a driving voltage to at least one LED. The PWM controller provides a PWM signal. The current source provides a driving current flowing through the LED when a dimming control signal is asserted. The signal controller turns off the switch when the dimming control signal is de-asserted and relays the PWM signal from the PWM controller to the switch so that the switch is controlled by the PWM signal when the dimming control signal is asserted.

Abstract: A driving circuit for a light emitting diode (LED) and a method thereof are provided. The driving circuit includes a voltage converting circuit and a reference voltage generator. The reference voltage generator generates a reference voltage according to the cathode voltage of the LED. The voltage converting circuit automatically adjusts the driving voltage of the LED based on the reference voltage so as to reduce the possibility of unnecessary power wastage caused by high driving voltage.

Abstract: A circuit and a method for driving light emitting diodes (LEDs) are provided. First, an input voltage is converted into an output voltage and the output voltage is transmitted to the anode terminals of LED strings. The output voltage is reduced when the output voltage is greater than a first threshold voltage and the output voltage is reduced when the lowest level among the cathode terminal voltages of all the LED strings is greater than a second threshold voltage. Thus, the output voltage can be maintained at a lower level for driving all the LED strings to reduce unnecessary power wastage.

Abstract: A light-emitting diode driving circuit includes a control circuit, a transistor switch and a compensating circuit. The control circuit receives an oscillating signal to generate a pulse drive signal. The transistor switch is activated by the pulse drive signal such that an inductor is charged by an input voltage, in which the inductor is arranged to deliver an inducting current to at least one light-emitting diode when the transistor switch is deactivated. The compensating circuit is coupled between the control circuit and a capacitor provided for reducing ripples of an output voltage corresponding to the inducting current. The compensating circuit performs a charging and discharging operation along with the capacitor when controlled by a dimming control signal provided to control brightness of the light-emitting diode.