Systems and methods are disclosed for wide frequency range voltage controlled oscillators. For example, an apparatus includes a Voltage Controlled Oscillator (VCO) including a delay cell which includes first and second current sources provided in parallel with one another. The first current source is controlled by a voltage control input connected to a voltage control terminal and the second current source is controlled by a bias voltage input connected to a bias voltage terminal. The first current source provides an alternate current path in the delay cell when the second current source is off. The delay cell is operable to receive an input and produce an output using the alternate current path.

An apparatus includes a first oscillator circuit coupled to a first electrode and a second oscillator circuit coupled to a second electrode. The first and second oscillator circuits oscillate synchronously in response to a capacitance between the first and second electrodes being greater than or equal to a threshold coupling capacitance and asynchronously in response to the capacitance being less than the threshold coupling capacitance. The first and second electrodes are separated by a distance, such that a disturbance within the distance increases the capacitance between the electrodes equal to or above the threshold coupling capacitance. The frequency of the first oscillator circuit is inversely proportional to a capacitance of the first electrode, and the frequency of the second oscillator circuit is inversely proportional to a capacitance of the second electrode.

A semiconductor device includes: a voltage generation unit that generates a first voltage having a first temperature characteristic; a constant voltage generation unit that generates a constant voltage; and an adjustment unit that generates a second voltage having a second temperature characteristic and a third voltage having a third temperature characteristic using the first voltage and the constant voltage. The constant voltage generation unit generates the constant voltage independently of the adjustment unit. One of the second and third temperature characteristics is an opposite characteristic to the first temperature characteristic. The device can also include a control unit that selects one of the second and third voltages in response to a predetermined setting value.

The present disclosure provides an oscillator circuit, a chip and an electronic device. The oscillator circuit includes two charge and discharge circuits, a reference voltage switching module, two comparators and a logic control module. When an output of either of the comparators, the logic control module controls one charge and discharge circuit connected to the comparator to discharge, controls the other charge and discharge circuit to charge, and controls the reference voltage switching module to switch a reference voltage of the comparator to a second voltage. When the output of the comparator transitions back, the logic control module controls the one charge and discharge circuit to charge. When the output of the comparator transitions again, the logic control module controls the reference voltage switching module to switch the reference voltage of the comparator to a first voltage, and controls one charge and discharge circuit to stop charging.

The present disclosure provides an oscillator circuit, a chip and an electronic device. The oscillator circuit includes two charge and discharge circuits, a reference voltage switching module, two comparators and a logic control module. When an output of either of the comparators, the logic control module controls one charge and discharge circuit connected to the comparator to discharge, controls the other charge and discharge circuit to charge, and controls the reference voltage switching module to switch a reference voltage of the comparator to a second voltage. When the output of the comparator transitions back, the logic control module controls the one charge and discharge circuit to charge. When the output of the comparator transitions again, the logic control module controls the reference voltage switching module to switch the reference voltage of the comparator to a first voltage, and controls one charge and discharge circuit to stop charging.

The present disclosure relates to a frequency modulation device, a switching power supply and a frequency modulation method thereof. The device includes: a waveform generation unit (10) configured to generate a periodic signal required for performing frequency modulation on a clock signal of a switching power supply to be controlled; a frequency modulation unit (20) configured to perform voltage-current conversion and arithmetic processing based on the periodic signal to obtain a frequency modulation current required for performing the frequency modulation on the clock signal of the switching power supply to be controlled; and an RC oscillation unit (30) configured to perform RC oscillation processing based on the frequency modulation current to obtain a frequency oscillation signal as the clock signal of the switching power supply to be controlled.

An oscillation circuit includes a delay circuit that includes a first inverter having an input terminal connected to a first node, a delay adjustment circuit including first and second current supply paths through which the first node is charged in response to an output signal of the delay circuit. During charging of the first node, a current with positive temperature characteristics is supplied to the first node through the first current supply path, and a current with negative temperature characteristics is supplied to the first node through the second current supply path.

A pulse-width modulation circuit includes an oscillator stage. The oscillator stage includes a first voltage comparator having a first input terminal, a second input terminal and an output terminal. A first capacitor is coupled to the first input terminal of the first voltage comparator. A charging path for the first capacitor is coupled between the first capacitor and the output terminal of the first voltage comparator, the charging path having a first resistance. A discharging path for the first capacitor is coupled between the first capacitor and the output terminal of the first voltage comparator, the discharging path having a second resistance that is different from the first resistance. A duty cycle of a clock signal generated by the oscillator stage is determined based on a first RC time constant for charging the first capacitor and a second RC time constant for discharging the first capacitor.

Various implementations described herein are directed to an integrated circuit. The integrated circuit may include a comparator stage, a resistor, a capacitor, and active switches arranged to provide a clock signal having a time period that is independent of a first source voltage. Independence may be achieved by using a second source voltage derived from the first source voltage as a fixed ratio.

A circuit device includes a control circuit that operates on the basis of a master clock signal, and an interface circuit that includes a register unit and transmits data on the basis of an external clock signal which is input from an external device. In addition, the register unit takes up error information of the master clock signal on the basis of the external clock signal and stores the taken-up error information. The interface circuit transmits the data, including the error information stored in the register unit.