An oscillator circuit includes a current controller, a first capacitor and a second capacitor. A current generator is coupled to the current controller, the first and the second capacitor, and is operable, under control of a control signal of the current controller, provide charging currents. A comparator stage comprises a first input coupled to the first capacitor, a second input coupled to the second capacitor and a reference input to be supplied with the reference voltage. The comparator stage further includes an oscillator output to provide a clock signal based on a comparison of the capacitor voltages and the reference voltage, respectively. A modulation circuit comprises an oscillator input to input the clock signal, a reference output is connected to the current generator, and is operable to alternate between the charging currents, such that a charging current is provided as reference current at the reference output and at least one charging current is provided to alternately charge/discharge the first capacitor and the second capacitor to respective capacitor voltages.

Embodiments of this application disclose an RC oscillator. The RC oscillator may amplify a difference between a first voltage and a second voltage by using a first amplifier and a second amplifier. The first amplifier may include a first amplification circuit and a second amplification circuit. The first amplification circuit and the second amplification circuit may share a same voltage-current conversion circuit. The RC oscillator disclosed in the embodiments of this application can not only avoid noise introduced by the first amplifier, but also reduce internal noise of the RC oscillator. This reduces a jitter of a clock signal.

A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a sense resistor, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the sense resistor. The system may additionally include a modulator for generating a differential pulse-width modulation driving signal to the first high-side switch, the second high-side switch, the first low-side switch, and the second low-side switch and pilot tone injection circuitry configured to inject a periodic pilot tone into the differential pulse-width modulation driving signal at a pilot tone frequency.

A semiconductor device with reduced power consumption is provided. The semiconductor device includes a node ND1, a node ND2, a resistor, a capacitor, and a comparison circuit. The resistor is electrically connected in series between one of a positive electrode and a negative electrode of a secondary battery and a first terminal. The resistor has a function of converting current flowing between the one of the positive electrode and the negative electrode of the secondary battery and the first terminal into a first voltage. The first voltage is added to a voltage of the node ND2 through the capacitor. The comparison circuit has a function of comparing a voltage of the node ND1 and the voltage of the node ND2. The comparison circuit outputs a signal that notifies detection of overcurrent when the voltage of the node ND2 is higher than the voltage of the node ND1.

A semiconductor device with reduced power consumption is provided. The semiconductor device includes a node ND1, a node ND2, a resistor, a capacitor, and a comparison circuit. The resistor is electrically connected in series between one of a positive electrode and a negative electrode of a secondary battery and a first terminal. The resistor has a function of converting current flowing between the one of the positive electrode and the negative electrode of the secondary battery and the first terminal into a first voltage. The first voltage is added to a voltage of the node ND2 through the capacitor. The comparison circuit has a function of comparing a voltage of the node ND1 and the voltage of the node ND2. The comparison circuit outputs a signal that notifies detection of overcurrent when the voltage of the node ND2 is higher than the voltage of the node ND1.

The disclosure discloses an RC oscillating circuit. A first end of a capacitor is grounded, a second end of the capacitor is connected to a charging path, a discharging path and a comparator, A first input end of a comparator is connected to first reference voltage. An output end of the comparator outputs a first output signal and is connected to a control end of the discharging path. The first reference voltage provides the flipped voltage of the comparator The first output signal forms an output clock signal. A first regulating circuit is configured to regulate the magnitude of the charging current and realize coarse frequency tuning. A second regulating circuit is configured to regulate the magnitude of the first reference voltage and realize fine frequency tuning. The disclosure has the advantages of low power consumption, fast start, high precision and wide tuning range.

The disclosure discloses an RC oscillating circuit. A first end of a capacitor is grounded, a second end of the capacitor is connected to a charging path, a discharging path and a comparator, A first input end of a comparator is connected to first reference voltage. An output end of the comparator outputs a first output signal and is connected to a control end of the discharging path. The first reference voltage provides the flipped voltage of the comparator The first output signal forms an output clock signal. A first regulating circuit is configured to regulate the magnitude of the charging current and realize coarse frequency tuning. A second regulating circuit is configured to regulate the magnitude of the first reference voltage and realize fine frequency tuning. The disclosure has the advantages of low power consumption, fast start, high precision and wide tuning range.

A relaxation oscillator and a method of controlling the relaxation oscillator are disclosed. The relaxation oscillator includes a reference voltage generating circuit configured to generate a reference voltage based on a transistor-based resistor, a variable voltage generating circuit configured to generate a variable voltage based on the reference voltage and a control switch, a threshold voltage generating circuit configured to generate a threshold voltage using a switched-capacitor resistor circuit, and a switch control circuit configured to output a control signal to control the control switch based on the variable voltage and the threshold voltage.

A relaxation oscillator and a method of controlling the relaxation oscillator are disclosed. The relaxation oscillator includes a reference voltage generating circuit configured to generate a reference voltage based on a transistor-based resistor, a variable voltage generating circuit configured to generate a variable voltage based on the reference voltage and a control switch, a threshold voltage generating circuit configured to generate a threshold voltage using a switched-capacitor resistor circuit, and a switch control circuit configured to output a control signal to control the control switch based on the variable voltage and the threshold voltage.

An oscillator includes a first current source, a second current source, a first chopper circuit, a resistive component, a capacitive component, and a processing circuit. The first current source provides a first current. The second current source provides a second current. The first chopper circuit includes a first terminal coupled to the first current source, a second terminal coupled to the second current source, a third terminal coupled to the resistive component, and a fourth terminal coupled to the capacitive component. The processing circuit generates an output clock in response to a first voltage across the resistive component and a second voltage across the capacitive component. The first chopper circuit couples the first terminal and the second terminal to the third terminal and the fourth terminal, respectively and alternately. The resistive component and the capacitive component receive the first current and the second current, respectively and alternately.