Abstract: A voltage-controlled oscillator includes a voltage-current converter, a first ring oscillator and a second ring oscillator. The voltage-current converter includes a first transistor for receiving a first control voltage at its gate terminal, a second transistor for receiving a second control voltage at its gate terminal, a third transistor connected to the first transistor in series and has a gate terminal connected to a drain terminal of the first transistor, a fourth transistor connected to the second transistor in series and has a gate terminal connected to a drain terminal of the second transistor, a resistor connected to a source terminal of the first transistor and a source terminal of the second transistor, a fifth transistor having a gate terminal connected to the drain terminal of the first transistor, and a sixth transistor having a gate terminal connected to the drain terminal of the second transistor.

Abstract: A voltage-controlled oscillator includes a voltage-current converter, a first ring oscillator and a second ring oscillator. The voltage-current converter includes a first transistor for receiving a first control voltage at its gate terminal, a second transistor for receiving a second control voltage at its gate terminal, a third transistor connected to the first transistor in series and has a gate terminal connected to a drain terminal of the first transistor, a fourth transistor connected to the second transistor in series and has a gate terminal connected to a drain terminal of the second transistor, a resistor connected to a source terminal of the first transistor and a source terminal of the second transistor, a fifth transistor having a gate terminal connected to the drain terminal of the first transistor, and a sixth transistor having a gate terminal connected to the drain terminal of the second transistor.

Abstract: An A-type converter circuit compares an input voltage with multiple threshold voltages, judges which segment it belongs to, and generates first and second voltages with the input voltage segment between them. The A-type converter circuit generates third and fourth voltages by amplifying the differences between the first and the input voltages and between the second and the input voltages. A B-type converter circuit divides the range between the third and fourth voltages into multiple segments, and judges which segment includes the common voltage. Subsequently, the B-type converter circuit generates fifth and sixth voltages with the common voltage segment between them. The B-type converter circuit generates a seventh (the next stage's third voltage) and an eighth voltage by amplifying the differences between the fifth and the common voltages and between the sixth and the common voltages.

Abstract: An A-type converter circuit compares an input voltage with multiple threshold voltages, judges which segment it belongs to, and generates first and second voltages with the input voltage segment between them. The A-type converter circuit generates third and fourth voltages by amplifying the differences between the first and the input voltages and between the second and the input voltages. A B-type converter circuit divides the range between the third and fourth voltages into multiple segments, and judges which segment includes the common voltage. Subsequently, the B-type converter circuit generates fifth and sixth voltages with the common voltage segment between them. The B-type converter circuit generates a seventh (the next stage's third voltage) and an eighth voltage by amplifying the differences between the fifth and the common voltages and between the sixth and the common voltages.

Abstract: To provide a comparator and an A/D converter having the comparator. The comparator includes a differential amplifier circuit section and a differential latch circuit section. A first input voltage signal, a second input voltage signal and a clock signal are inputted to the differential amplifier circuit section. The differential amplifier circuit section operates base on the clock signal to output a first output voltage signal and a second output voltage signal which respectively correspond to the value the input voltage signal and the value of the reference voltage signal and are amplified. The differential latch circuit section operates based on the first and second output voltage signals to keep and output a comparison result between the first input voltage signal and the second input voltage signal.

Abstract: To provide a comparator and an A/D converter having the comparator. The comparator includes a differential amplifier circuit section and a differential latch circuit section. A first input voltage signal, a second input voltage signal and a clock signal are inputted to the differential amplifier circuit section. The differential amplifier circuit section operates base on the clock signal to output a first output voltage signal and a second output voltage signal which respectively correspond to the value the input voltage signal and the value of the reference voltage signal and are amplified. The differential latch circuit section operates based on the first and second output voltage signals to keep and output a comparison result between the first input voltage signal and the second input voltage signal.

Abstract: Provided is a DAC with tuning circuitry in accordance with some embodiments for tuning current sources in the DAC. The DAC may be used for a sigma-delta converter in some embodiments.