Abstract: Disclosed is a voltage-controlled oscillator (VCO) capable of providing an effective high VCO gain against slow change of an input voltage caused by the variation of manufacturing processes, temperature, voltage, etc. and providing an effective low VCO gain against rapid change of the input voltage for reducing jitter. The VCO includes: an input circuit generating an input current according to an input voltage; a first current supply circuit generating a first output current according to the input current; a second current supply circuit generating a second output current according to the input current; a filter coupled to the input circuit and the second current supply circuit and configured to slow down the influence caused by the variation of the input current on the second current supply circuit; and an oscillating circuit generating an output clock according to the first output current and the second output current.

Abstract: An impedance calibration device provided includes a timing device, a first transmitter, a first variable resistor, a second variable resistor and a first receiver. The first variable resistor is used to receive a first adjustment code. The second variable resistor is used to receive a second adjustment code. The first receiver generates a first contact digital signal according to a first contact voltage. The first receiver generates a first terminate digital signal according to a first terminate voltage and the first adjustment code. The first receiver generates a first load digital signal according to a load voltage and the second adjustment. The timing device dynamically adjust the first adjustment code and the second adjustment code according to the first contact digital signal, the first terminate digital signal and the first load digital signal.

Abstract: An impedance calibration device provided includes a timing device, a first transmitter, a first variable resistor, a second variable resistor and a first receiver. The first variable resistor is used to receive a first adjustment code. The second variable resistor is used to receive a second adjustment code. The first receiver generates a first contact digital signal according to a first contact voltage. The first receiver generates a first terminate digital signal according to a first terminate voltage and the first adjustment code. The first receiver generates a first load digital signal according to a load voltage and the second adjustment. The timing device dynamically adjust the first adjustment code and the second adjustment code according to the first contact digital signal, the first terminate digital signal and the first load digital signal.

Abstract: The present invention discloses an electrostatic discharge (ESD) protection circuit, including: a first terminal configured to receive a first voltage; a second terminal configured to receive a second voltage; a detection voltage generating circuit configured to provide a detection voltage according to the first voltage and the second voltage; a warning circuit configured to generate a control signal according to the detection voltage, in which the control signal indicates a normal condition when the detection voltage satisfies predetermined voltage setting, and the control signal indicates an abnormal condition when the detection voltage does not satisfy the predetermined voltage setting; and a protected circuit configured to carry out a self-protection operation when receiving the control signal indicating the abnormal condition.

Abstract: A power supply device includes a power supply circuit, a detection circuit, and a control circuit. The power supply circuit is configured to output a supply voltage. The detection circuit is configured to sequentially provide a first predetermined resistance and a second predetermined resistance according to a plurality of switching signals, in order to operate with an electronic device and the supply voltage to sequentially obtain a first detection voltage and a second detection voltage. The control circuit is configured to generate the switching signals, and determine a load resistance of the electronic device according to the first detection voltage and the second detection voltage. The control circuit is further configured to determine whether the load resistance is within a predetermined resistance range, and the power supply circuit is further configured to drive the electronic device if the load resistance is within the predetermined resistance range.

Abstract: A switch circuit comprising: a plurality of switches; a switching module; and a capacitor, having a first terminal and a second terminal, wherein the first terminal is coupled to a predetermined voltage, and the second terminal is coupled to a control terminal of at least the switch in a conductive mode via the switching module, to thereby control a conductive state for the at least one switch.

Abstract: A pulse generation circuit, for outputting a pulse signal at an output terminal, comprises a PMOS, an NMOS and a logic circuit. The PMOS has a source coupled to a first reference voltage level, a drain coupled to the output terminal, and a gate coupled to a first gate control signal. The NMOS has a source coupled to a second reference voltage level, a drain coupled to the output terminal, and a gate coupled to a second gate control signal. The logic circuit generates the first gate control signal according to a control signal and a first logic signal, relating to the second gate control signal and a delay signal of the second gate control signal, and generates the second gate control signal according to the control signal and a second logic signal, relating to the first gate control signal and a delay signal of the first control signal.

Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; an internal node; a first divider resistor positioned between the first signal node and the internal node; a second divider resistor positioned between the second signal node and the internal node; a comparing circuit for comparing a divided voltage at the internal node with a reference voltage to generate a comparison signal; and an adjusting circuit for adjusting resistance of at least one of the first and second adjustable resistors according to the comparison signal.

Abstract: The present invention discloses a clock generator comprising: an oscillator operable to generate a reference clock; a multi-phase clock generating circuit operable to generate a plurality of output clocks of the same frequency but different phases according to the reference clock and stop or start outputting the output clocks according to a power control signal; a sequential clock gating circuit operable to sequentially stop or start outputting a plurality of gated clocks according to a gate control signal and maintain an output cycle number relation between the gated clocks even though the multi-phase clock generating circuit stops and then starts outputting the output clocks; and a clock operation control circuit operable to provide the power control signal and the gate control signal.

Abstract: A pulse generation circuit for outputting a pulse signal at an output terminal, including: a PMOS, an NMOS, and a logic circuit. The PMOS has a source coupled to a first reference voltage level, a drain coupled to the output terminal, and a gate that receives a first gate control signal. The NMOS has a source coupled to a second reference voltage level, a drain coupled to the output terminal, and a gate that receives a second gate control signal. The logic circuit generates the first gate control signal according to a control signal and a first delay signal and generates the second gate control signal according to the control signal and a second delay signal. The first delay signal is relevant to the second gate control signal and the control signal. The second delay signal is relevant to the first gate control signal and the control signal.

Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; a first voltage difference generating circuit coupled with two terminals of the first adjustable resistor to generate a first voltage difference value; a second voltage difference generating circuit coupled with two terminals of the second adjustable resistor to generate a second voltage difference value; sample-and-hold circuits for generating sampled signals according to the first voltage difference value and the second voltage difference value; a comparing circuit for comparing the sampled signals; and an adjusting circuit for adjusting resistance of the first and/or second adjustable resistors accor

Abstract: This invention discloses a signal transmitting and receiving circuit of a digital subscriber line used for transmitting an output signal to a telecommunication loop or receiving an input signal from the telecommunication loop. The signal transmitting and receiving circuit comprises a transformer, which is coupled to the telecommunication loop; a signal transmitting module, which is coupled to the transformer, for generating the output signal; a signal receiving module, which is coupled to the transformer, for processing the input signal; an echo cancelling circuit, comprising passive components and having two ends, one of which is coupled to the signal transmitting module and the transformer, the other is coupled to the signal receiving module and the transformer. The output signal is transmitted to the telecommunication loop via the electromagnetic coupling of the transformer, and the input signal is received by the signal receiving module by the electromagnetic coupling of the transformer.

Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; an internal node; a first divider resistor positioned between the first signal node and the internal node; a second divider resistor positioned between the second signal node and the internal node; a comparing circuit for comparing a divided voltage at the internal node with a reference voltage to generate a comparison signal; and an adjusting circuit for adjusting resistance of at least one of the first and second adjustable resistors according to the comparison signal.

Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; a first voltage difference generating circuit coupled with two terminals of the first adjustable resistor to generate a first voltage difference value; a second voltage difference generating circuit coupled with two terminals of the second adjustable resistor to generate a second voltage difference value; sample-and-hold circuits for generating sampled signals according to the first voltage difference value and the second voltage difference value; a comparing circuit for comparing the sampled signals; and an adjusting circuit for adjusting resistance of the first and/or second adjustable resistors accor

Abstract: The present invention discloses a clock generator comprising: an oscillator operable to generate a reference clock; a multi-phase clock generating circuit operable to generate a plurality of output clocks of the same frequency but different phases according to the reference clock and stop or start outputting the output clocks according to a power control signal; a sequential clock gating circuit operable to sequentially stop or start outputting a plurality of gated clocks according to a gate control signal and maintain an output cycle number relation between the gated clocks even though the multi-phase clock generating circuit stops and then starts outputting the output clocks; and a clock operation control circuit operable to provide the power control signal and the gate control signal.

Abstract: A pulse generation circuit for outputting a pulse signal at an output terminal, including: a PMOS, an NMOS, and a logic circuit. The PMOS has a source coupled to a first reference voltage level, a drain coupled to the output terminal, and a gate that receives a first gate control signal. The NMOS has a source coupled to a second reference voltage level, a drain coupled to the output terminal, and a gate that receives a second gate control signal. The logic circuit generates the first gate control signal according to a control signal and a first delay signal and generates the second gate control signal according to the control signal and a second delay signal. The first delay signal is relevant to the second gate control signal and the control signal. The second delay signal is relevant to the first gate control signal and the control signal.

Abstract: A pulse generation circuit, for outputting a pulse signal at an output terminal, comprises a PMOS, an NMOS and a logic circuit. The PMOS has a source coupled to a first reference voltage level, a drain coupled to the output terminal, and a gate coupled to a first gate control signal. The NMOS has a source coupled to a second reference voltage level, a drain coupled to the output terminal, and a gate coupled to a second gate control signal. The logic circuit generates the first gate control signal according to a control signal and a first logic signal, relating to the second gate control signal and a delay signal of the second gate control signal, and generates the second gate control signal according to the control signal and a second logic signal, relating to the first gate control signal and a delay signal of the first control signal.

Abstract: A signal generating apparatus, for generating a power-on-reset signal, including a bias circuit and a power-on-reset signal generating circuit is disclosed. The bias circuit is for generating an output bias voltage, and includes at least one bipolar junction transistor (BJT), wherein a base terminal of the BJT is coupled to a collector terminal of the BJT, and the output bias voltage is related to an emitter-to-base voltage of the BJT. The power-on-reset signal generating circuit is coupled to the bias circuit, and is for generating a duplicated voltage by duplicating the output bias voltage, wherein the power-on-reset signal is generated according to the duplicated voltage.

Abstract: An impedance calibration device includes: a variable impedance, an operational unit, an analog-digital converter, and a controller. The operational unit receives a first analog signal and a second analog signal, and performs a difference operation to generate an output voltage. The analog-digital converter generates an adjustment code according to the output voltage. The controller is coupled to the analog-digital converter and the variable impedance, and adjusts a resistance value of the variable impedance according to the adjustment code.

Abstract: This invention discloses a signal transmitting and receiving circuit of a digital subscriber line used for transmitting an output signal to a telecommunication loop or receiving an input signal from the telecommunication loop. The signal transmitting and receiving circuit comprises a transformer, which is coupled to the telecommunication loop; a signal transmitting module, which is coupled to the transformer, for generating the output signal; a signal receiving module, which is coupled to the transformer, for processing the input signal; an echo cancelling circuit, comprising passive components and having two ends, one of which is coupled to the signal transmitting module and the transformer, the other is coupled to the signal receiving module and the transformer. The output signal is transmitted to the telecommunication loop via the electromagnetic coupling of the transformer, and the input signal is received by the signal receiving module by the electromagnetic coupling of the transformer.