A local oscillator buffer circuit comprises a complementary common-source stage comprising a first p-channel transistor (MCSP) and a first n-channel transistor (MCSN), arranged such that their respective gate terminals are connected together at a first input node, and their respective drain terminals of each of is connected together at a buffer output node. A complementary source-follower stage comprises a second p-channel transistor (MSFP) and a second n-channel transistor (MSFN), arranged such that their respective gate terminals are connected together at a second input node, and their respective source terminals are connected together at the buffer output node.

A local oscillator buffer circuit comprises a complementary common-source stage comprising a first p-channel transistor (MCSP) and a first n-channel transistor (MCSN), arranged such that their respective gate terminals are connected together at a first input node, and their respective drain terminals of each of is connected together at a buffer output node. A complementary source-follower stage comprises a second p-channel transistor (MSFP) and a second n-channel transistor (MSFN), arranged such that their respective gate terminals are connected together at a second input node, and their respective source terminals are connected together at the buffer output node.

An oscillator circuit includes a first comparator that outputs a first signal indicative of a comparison result between an input potential and a threshold, a second comparator that outputs a second signal indicative of a comparison result between an input potential and the threshold, a RS flip-flop circuit that receives the first signal and the second signal and outputs first and second oscillation signals, a first charge/discharge unit that charges and discharges a first capacitor based on the first oscillation signal, a second charge/discharge unit that charges and discharges a second capacitor based on the second oscillation signal, a first dummy switch controlled to be on and off according to the second oscillation signal and adding a predetermined capacity to a first node, and a second dummy switch controlled to be on and off according to the first oscillation signal and adding a predetermined capacity to a second node.

An oscillator circuit includes a first comparator that outputs a first signal indicative of a comparison result between an input potential and a threshold, a second comparator that outputs a second signal indicative of a comparison result between an input potential and the threshold, a RS flip-flop circuit that receives the first signal and the second signal and outputs first and second oscillation signals, a first charge/discharge unit that charges and discharges a first capacitor based on the first oscillation signal, a second charge/discharge unit that charges and discharges a second capacitor based on the second oscillation signal, a first dummy switch controlled to be on and off according to the second oscillation signal and adding a predetermined capacity to a first node, and a second dummy switch controlled to be on and off according to the first oscillation signal and adding a predetermined capacity to a second node.

An oscillator equipped with a temperature compensation circuit is illustrated. Through the temperature compensation circuit, a transistor of a current mirror circuit of the oscillator which outputs a reference current to a voltage matching circuit is controlled by the temperature compensation voltage. Both of the temperature compensation voltage and a reference current decrease as the temperature rises, and a delay time of the oscillation voltage is proportional to the temperature compensation voltage and inversely proportional to the reference current. Therefore, the effects of temperature on the delay time just cancel each other out. The delay time of the oscillating voltage is related to the frequency of the clock signal. Therefore, if the delay time of the oscillating voltage is not affected by temperature, the frequency of the clock signal will not be affected by temperature.

An oscillator equipped with a temperature compensation circuit is illustrated. Through the temperature compensation circuit, a transistor of a current mirror circuit of the oscillator which outputs a reference current to a voltage matching circuit is controlled by the temperature compensation voltage. Both of the temperature compensation voltage and a reference current decrease as the temperature rises, and a delay time of the oscillation voltage is proportional to the temperature compensation voltage and inversely proportional to the reference current. Therefore, the effects of temperature on the delay time just cancel each other out. The delay time of the oscillating voltage is related to the frequency of the clock signal. Therefore, if the delay time of the oscillating voltage is not affected by temperature, the frequency of the clock signal will not be affected by temperature.

An device having an oscillator circuit modifiable between a first operating mode and a second operating mode, wherein the first operating mode has a first frequency accuracy and a first power consumption, wherein the second operating mode has a second frequency accuracy and a second power consumption, wherein the second frequency accuracy is more accurate than the first frequency accuracy and the second power consumption is higher than the first power consumption, and a control circuit in communication with the oscillator circuit to modify the operating mode of the oscillator circuit.

An device having an oscillator circuit modifiable between a first operating mode and a second operating mode, wherein the first operating mode has a first frequency accuracy and a first power consumption, wherein the second operating mode has a second frequency accuracy and a second power consumption, wherein the second frequency accuracy is more accurate than the first frequency accuracy and the second power consumption is higher than the first power consumption, and a control circuit in communication with the oscillator circuit to modify the operating mode of the oscillator circuit.

According to at least some example embodiments of the inventive concepts, an RC oscillator includes an oscillator core including a timing-circuit that includes a plurality of matched current sources, a plurality of capacitors, and a resistor, a first continuous time comparator, and a Schmitt trigger; and an analog circuit connected to the oscillator core including a second continuous time comparator representing a replica of the first continuous time comparator, and an EX-OR gate, wherein the analog circuit is configured to pass a clock signal of the oscillator core through the second continuous time comparator and obtaining a delayed clock signal representing a comparator delay, extract the comparator delay of the first continuous time comparator based on feeding the clock signal and the obtained delayed clock signal to the EX-OR gate, and charge the plurality of capacitors connected to the first continuous time comparator.

According to at least some example embodiments of the inventive concepts, an RC oscillator includes an oscillator core including a timing-circuit that includes a plurality of matched current sources, a plurality of capacitors, and a resistor, a first continuous time comparator, and a Schmitt trigger; and an analog circuit connected to the oscillator core including a second continuous time comparator representing a replica of the first continuous time comparator, and an EX-OR gate, wherein the analog circuit is configured to pass a clock signal of the oscillator core through the second continuous time comparator and obtaining a delayed clock signal representing a comparator delay, extract the comparator delay of the first continuous time comparator based on feeding the clock signal and the obtained delayed clock signal to the EX-OR gate, and charge the plurality of capacitors connected to the first continuous time comparator.