Abstract: The present invention provides a level shift circuit capable of operating at low input voltage. The level shift circuit comprises: a first switch element coupled to a first output terminal, a second switch element coupled to a second output terminal, a third switch element coupled to the second output terminal and the first output terminal, a fourth switch element coupled to the first output terminal and the second output terminal, a first current source module for letting a current passing through the third switch element smaller than a current passing through the first switch element when the first switch element and the third switch element are conducted, and a second current source module for let a current passing through the fourth switch element smaller than a current passing through the second switch element when the second switch element and the fourth switch element are conducted.

Abstract: A direct injection-locked frequency divider circuit with inductive-coupling feedback architecture is proposed, which is designed for integration to a high-frequency circuit system with a high operating frequency such as 24 GHz (gigahertz), for providing a frequency-dividing function. The proposed frequency divider circuit comprises an injection-locked oscillator (ILO) circuit module and a pair of buffer-stage circuits, wherein the ILO circuit module further includes a signal-injection circuit, a cross-coupled switching circuit, and a variable-capacitance tuning circuit. The proposed circuit architecture is characterized by the circuit arrangement of a direct-injection architecture and an inductive-coupling feedback architecture by coupling the inductive elements of the buffer-stage circuits to the inductive elements of the variable-capacitance tuning circuit in the ILO circuit module.

Abstract: A voltage level shifter with voltage boost mechanism is disclosed for interfacing two circuit units having different operating voltage swings. The voltage level shifter includes a first inverter, a second inverter, a first capacitor, a second capacitor and a plurality of transistors. The input and power ends of the first inverter function to receive an input voltage and a first voltage respectively. The output end of the second inverter functions to provide an output voltage. When the input voltage is a ground voltage, the output voltage is also a ground voltage; meanwhile, the switches are controlled for charging the first and second capacitors to a second voltage and a third voltage respectively. When the input voltage is the first voltage, a sum voltage of the first, second, and third voltages is furnished to the power end of the second inverter for providing the sum voltage as the output voltage.

Abstract: A high-side driver in a driver circuit for driving a half-bridge stage having high- and low-side power switching devices series connected at a switched node, the high-side driver driving the high-side power switching device.

Abstract: A sampling circuit according to correlated double sampling to generate a difference of two voltages at a sampling node, with the second voltage representing the sum of an input signal and an offset, and the first voltage representing the offset alone. In an embodiment, a first capacitor is charged to the first voltage in a first phase. A second capacitor is then charged to the second voltage in a second phase. In a third phase, the first capacitor is coupled to the input terminal of the amplifier and the second capacitor is coupled between the input and output terminals of the amplifier to cause the amplifier to generate the difference of the first and second voltages. The first capacitor has a capacitance much less than the second capacitor, thereby minimizing the noise power at the output of the amplifier.

Abstract: Disclosed is a voltage switch circuit of a semiconductor device. The subject voltage switch circuit can be used to apply voltage to a semiconductor memory device control circuit. The voltage switch circuit according to an embodiment includes five transistors and a capacitor. An output terminal of the subject circuit outputs VSS when VDD is applied to an input terminal, and outputs a boosted operating voltage when VSS is applied to the input terminal.

Abstract: A clock signal transmission circuit having a variable initial value for a wait time that is required until a clock signal stabilizes. The clock signal is generated from an original clock signal. The wait time setting unit generates a plurality of wait time signals to wait until the original clock signal stabilizes before providing the clock signal to the internal circuit. A wait time determination unit selects one of the wait time signals and provides the selected wait time signal to a clock control unit. The wait time determination unit includes a data holding circuit which generates a selection signal in accordance with the initial value, a selection circuit which selects one of the wait time signals based on the selection circuit, and an initial value setting circuit enabling the initial value to be varied.

Abstract: A phase shift circuit that includes two, rather than four, delay chains and corresponding selectors is described. This provides a significant area savings and reduces the intrinsic delay of the phase shift circuit, which is particularly beneficial for embodiments in which there is no intrinsic delay matching. In one implementation, the phase shift circuit includes a first delay circuit and a matching delay circuit. The first delay circuit provides a first delay that includes a first intrinsic delay and a first intentional delay. The delay matching circuit provides a matching delay that matches the first intrinsic delay. In one implementation, the phase shift circuit also includes a second delay circuit to provide a second delay that includes a second intrinsic delay and second intentional delay, where the second intrinsic delay matches the first intrinsic delay and the second intentional delay is half as long as the first intentional delay.

Abstract: A triangle wave generator with function of spreading frequency spectrum is provided. The triangle wave generator includes a switch control circuit, a current generator, an integrator, and a spread spectrum control circuit. The switch control circuit provides an internal clock and a switch control signal. The current generator is coupled to the switch control circuit and provides charge current according to the switch control signal. The integrator is coupled to the current generator and provides a triangle wave signal. The spread spectrum control circuit is coupled to the switch control circuit and the current generator for providing a current control signal according to the internal clock.

Abstract: An exemplary circuit for turning on a motherboard comprises a first switch module comprising a first terminal arranged to receive a standby power and connected to a sixth terminal of a computer front panel header, a second terminal arranged to receive the standby power, and a control terminal; a timing circuit charged by a system power; and a second switch module comprising a first terminal connected to the control terminal of the first switch module via the timing circuit, a second terminal arranged to receive the standby power, and a control terminal arranged to receive the system power, wherein, when the system power is lost, the second switch module discharges the timing circuit for turning on the first switch module after a discharge time, and the motherboard is turned on when the first switch module is turned on to ground the sixth terminal of the computer front panel header.

Abstract: A dynamic voltage pump circuit includes a first stage voltage pump, a second stage voltage pump, a limiter, and a comparator. The first stage voltage pump generates an intermediate supply voltage according to an input supply voltage and a pump signal. The second stage voltage pump generates an output supply voltage according to the intermediate supply voltage, the pump signal, and an enable signal; the second stage voltage pump is enabled and disabled when the enable signal is asserted and de-asserted, respectively. The limiter controls the pump signal according to a comparison of the output supply voltage with a first reference voltage. The comparator compares the first reference voltage with a second reference voltage to generate the enable signal, and can assert the enable signal when the desired output supply voltage exceeds the maximum possible intermediate supply voltage generated by the first stage voltage pump.

Abstract: A low noise analog sampling circuit that includes a transistor connected to a first feedback loop and to a second feedback loop. During a second operational phase the second feedback loop provides the transistor a feedback signal that is responsive to an amplified error signal; wherein the error signal represents a difference between (i) a sampled signal representative of a state of the transistor short period before a first feedback loop was opened and (ii) a signal representative of a current state of the transistor; wherein at an end of the second operational phase the second feedback loop is opened and introduces a second noise that is attenuated by multiple capacitors.

Abstract: A phase-locked loop includes a processing unit, a voltage-controlled oscillator, and a control unit. The processing unit generates a control voltage to a node according to a phase difference between a reference clock and a first feedback clock. The voltage-controlled oscillator generates the first feedback clock according to a voltage of the node. The control unit deactivates the voltage-controlled oscillator and provides a start voltage to the node in a power-down mode, and activates the voltage-controlled oscillator to generate the first feedback clock according to the voltage of the node in a power-on mode. The control unit stops providing the start voltage in the power-on mode.

Abstract: A capacitive load driving device applies a multi-level voltage to a capacitive load to drive the capacitive load. In the capacitive load driving device, a voltage control signal generator unit generates a voltage control signal. A voltage amplifier unit amplifies a voltage of the voltage control signal. A current amplifier unit amplifies a current of an output of the voltage amplifier unit to perform charging of the capacitive load. A falling control signal generator unit generates a falling pulse having a predetermined pulse width when a width of falling of the voltage control signal exceeds a predetermined value. A switching unit performs discharging of the capacitive load in response to the falling pulse received.

Abstract: A method and an input signal level detection apparatus that correctly detect a level of an input signal while consuming low power apparatus including: a full-wave rectifier outputting a full-wave rectified waveform by performing a full-wave rectification on a first signal corresponding to an input signal, and on a second signal having a phase difference of 180 degrees from the first signal; a common voltage detector detecting a common voltage of the first signal and the second signal; and a level detection unit detecting a level of the input signal, based on a subtraction result obtained by subtracting the common voltage from the full-wave rectified waveform.

Abstract: A loop filter in a phase lock loop circuit comprising a reference precision resistor, a first FET and a second FET, wherein the gate of the first FET is tied to the gate of the second FET, and a filter capacitor connected to the first FET for producing a capacitor voltage. The capacitor voltage is applied to the source of the first FET, the source of the second FET, and to the bottom of the reference precision resistor acting as a virtual ground. The capacitor voltage generated by the filter capacitor sets the bias point of the second FET such that the second FET comprises characteristics of an integrated precision resistor. A predetermined voltage generated by the second FET is applied to the gate of the first FET to set the bias point of the first FET such that the first FET comprises characteristics of an integrated precision resistor.

Abstract: The present invention discloses a voltage output device for an electronic system, for transforming an input voltage for generating an output voltage for a load, which includes a first node, a second node, a third node, a first transistor, a second transistor, a first driving unit, a second driving unit, a control unit, a first diode, an inductor, a first capacitor, and a boost circuit.

Abstract: The present invention discloses a voltage output device for an electronic system, for transforming an input voltage for generating an output voltage for a load, which includes a first transistor, a second transistor, a first driving unit, a second driving unit, a control unit, a diode, an inductor, a first capacitor, and a boost circuit. The boost circuit includes a level shifter, a third transistor, and a second capacitor. Whether the third transistor 502 is turned on is synchronized with the second transistor 402, so as to prevent damage caused by a huge current passing through the third transistor when the second transistor is cut off.