Abstract: An integrator having an offset evaluation circuit and a collected charge reduction circuitry and method for using the integrator. The integrator includes an amplifier, operable to amplify an input signal, an integration capacitor for collecting charge indicative of a level of the input signal and an offset capacitor. The offset evaluation circuit is operable to charge the offset capacitor with charge corresponding to an offset voltage of the amplifier and the collected charge reduction circuitry is operable to collect charge resulting from disconnection of the offset evaluation circuit, thereby reducing an amount of charge and associated noise input to the amplifier.

Abstract: A switched capacitor amplifier circuit includes an operational amplifier, a first capacitor and a second capacitor each having one end connected to a negative input terminal of the operational amplifier, a first switching circuit configured to connect the other end of the first capacitor and a signal source during a first operation, a second switching circuit configured to connect the other end of the second capacitor and the output terminal of the operational amplifier so as to connect the output terminal and the negative input terminal of the operational amplifier through the second capacitor during the second operation, and an impedance converter circuit configured to convert an output impedance of the signal source into a specified impedance, the impedance converter circuit being connected between the first switching circuit and the other end of the first capacitor.

Abstract: Disclosed herein are related to a system and a method of amplifying an input voltage based on cascaded charge pump boosting. In one aspect, first electrical charges are stored at a first capacitor according to the input voltage to obtain a second voltage. In one aspect, the second voltage is amplified according to the first electrical charges stored by the first capacitor to obtain a third voltage. In one aspect, second electrical charges are stored at the second capacitor according to the third voltage. In one aspect, the third voltage is amplified according to the second electrical charges stored by the second capacitor to obtain a fourth voltage.

Abstract: A circuit includes a power detector and a logic circuit. The power detector is configured to output a first power management signal according to a first power supply signal from a first power supply and a status signal. The circuit is configured to operate in different modes in response to the status signal. The logic circuit is configured to output a second power management signal, according to the first power management signal and the status signal.

Abstract: First and second paths (I,II) are connected in parallel between an input terminal (IN) and an output terminal (OUT). A high-pass filter (HPF) is provided in the first path (I). A low-pass filter (LPF) is provided in the second path (II). A switch (SW1-SW4) connects one of the high-pass filter (HPF) and the low-pass filter (LPF) to the input terminal (IN) and the output terminal (OUT) and disconnects the other. A transmission line (TL1,TL2) is provided on the first and second paths (I,II) respectively. A line length of the transmission line (TL1,TL2) is adjusted such that a resonance caused due to circuit constants of the high-pass filter (HPF) and the low-pass filter (LPF) and capacitance obtained when the switch (SW1-SW4) is OFF is shifted to a communication frequency band.

Abstract: A multi-bit level shifter that has a plurality of level shifters, each of which is configured to receive an input signal in a first voltage domain and provide a corresponding output signal in a second voltage domain. The level shifters each have an enable node. An enable circuit includes an output terminal connected to the enable node of each of the plurality of level shifters, and each of the plurality of level shifters is configured to output the corresponding output signals in response an enable signal received by the enable circuit.

Abstract: A circuit having an input and an output, the circuit comprising: a first amplifier having a first input, a second input and an output coupled to the output of the circuit; a first capacitor having a first terminal coupled to the first input of the first amplifier and a second terminal coupled to the output of the first amplifier; a first resistor having a first terminal coupled to the first input of the first amplifier and a second terminal; a buffer having an output coupled to the second terminal of the first resistor and an input; a second resistor having a first terminal coupled to the output of the first amplifier and a second terminal coupled to the input of the buffer; a second capacitor coupled between the input of the buffer and ground; and a third resistor coupled between the input of the buffer and the input of the circuit.

Abstract: A reference voltage generating circuit includes a bandgap reference (BGR) circuit configured to output an active reference voltage at a first node according to a sample signal; a first charging circuit configured to charge a first capacitor using the active reference voltage according to the sample signal; a second charging circuit configured to charge a second capacitor using the active reference voltage according to the sample signal; and a comparing circuit configured to compare a voltage difference between a charge voltage of the first capacitor and a charge voltage of the second capacitor with a threshold value, wherein the sample signal is a pulse signal generated using an output of the comparing circuit and the charge voltage of the first capacitor is provided as a low power reference voltage in a low power operation mode.

Abstract: In a receiver that demodulates a received signal, deterioration of signal quality is suppressed. A current output unit generates and outputs, from a voltage signal, a current signal including a predetermined offset current in a low-frequency component between a high-frequency component having a frequency higher than a predetermined frequency and the low-frequency component having a frequency lower than the predetermined frequency. A demodulation unit demodulates the high-frequency component. A filter circuit passes, in the current signal, the high-frequency component from a current output unit to the demodulation unit, and causes the low-frequency component to flow from the current output unit to a predetermined reference potential point.

Abstract: An offset corrected bandgap reference and temperature sensor is disclosed. In a complementary metal-oxide-semiconductor (CMOS) bandgap reference, non-idealities in the operational amplifier (op-amp) bandgap reference circuit can lead to a voltage offset. This operational amplifier offset voltage is the dominant source of error in the bandgap reference. If the bandgap reference is used in a temperature sensor, it only needs to be accurate during the analog-to-digital conversion cycle. Embodiments of the present disclosure employ switched capacitors to store the operational amplifier offset during a sample mode in which the bandgap reference operates continuous-time. The operational amplifier offset is then corrected during a hold mode while the temperature sensor completes the analog-to-digital conversion.

Abstract: Dedicated circuitry may monitor a processor supply voltage and provide additional power on a temporary nano-second scale basis to the processor when the supply voltage drops below predetermined levels. This may be done without explicit knowledge of a commanded supply voltage level for the processor.

Abstract: A current sensor including a voltage generation circuit and a voltage integration circuit is provided. The voltage generation circuit is configured to generate a first voltage according to a current to be sensed. The voltage integration circuit is coupled to the voltage generation circuit and configured to receive the first voltage and a second voltage to generate an output voltage. The voltage integration circuit includes a first amplifier, a second amplifier and a first capacitor. The first amplifier is configured to receive the first voltage and the second voltage to generate a third voltage. The second amplifier is coupled to the first amplifier and configured to receive the third voltage to generate the output voltage. The first capacitor is coupled between an output terminal of the voltage generation circuit and an output terminal of the first amplifier and configured to reduce a voltage difference between the first voltage and the second voltage.

Abstract: A light-emitting display includes a display panel, a first circuit, and a second circuit. The display panel comprises a pixel. The first circuit supplies a data voltage to a data line for the pixel. The second circuit performs a sensing operation for sensing a sensing line for the pixel and outputs a voltage required for the sensing operation, and outputs a noise removing voltage for cancelling out noise formed on the sensing line during the sensing operation.

Abstract: A communication system includes a modulator configured to generate a modulated signal responsive to at least a data signal, and a demodulator configured to demodulate the modulated signal responsive to a first carrier signal. The demodulator includes a filter configured to generate a filtered first signal based on a first signal, and a gain adjusting circuit coupled to the filter. The first signal is based on the first carrier signal and modulated signal. The filter has a gain controlled by a set of control signals. The gain adjusting circuit is configured to adjust the gain of the filter, and to generate the set of control signals based on a voltage of the filtered first signal and a voltage of the first signal. The gain adjusting circuit includes a first peak detector coupled to the filter, and configured to detect a peak value of the voltage of the filtered first signal.

Abstract: A discrete time filter network with an input signal connection and an output signal connection and comprising a capacitor bank with a plurality of history capacitors, and at least one sampling capacitor which operates at a predetermined cycling rate to couple to at least one history capacitor at a time, which history capacitor is selected from the capacitor bank so as to share electrical charge between such selected history capacitor and the sampling capacitor, wherein there is a plurality of sampling capacitors that are provided in the capacitor bank, and the discrete time filter network is provided with at least one switch network comprising a plurality of clock driven switches for making selected cyclical connections between the sampling capacitors and the history capacitors in the capacitor bank at the predetermined cycling rate.

Abstract: Apparatus and methods for reducing charge injection mismatch are provided herein. In certain implementations, an electronic circuit includes one or more switch banks. Each switch bank can include a selection circuit and a plurality of switches that can be controlled using one or more clock signals. The selection circuit can select a first portion of the switches for operation in a first switch group and a second portion of the switches for operation in a second switch group. During a calibration, the electronic circuit's charge injection mismatch can be directly or indirectly observed for different switch configurations of the switch banks. The electronic circuit can be programmed to operate with the selected switch configurations of the switch banks to provide the electronic circuit with small charge injection mismatch.

Abstract: A filter and an operating method thereof are provided. The filter includes a logic circuit, a power circuit and a filter circuit. The logic circuit provides a switching control signal. The power circuit is coupled to the logic circuit. The filter circuit is coupled to the power circuit and the logic circuit. The filter circuit includes an amplifier, a first capacitor and a first transistor. An output end of the amplifier is coupled to the logic circuit, and provides an output signal. The first capacitor is coupled between an input end and output end of the amplifier. The first transistor is connected in parallel with the first capacitor. A control end of the first transistor is coupled to the power circuit. The logic circuit provides a switching control signal to the power circuit according to the output signal. The power circuit supplies a control voltage to the first transistor according to the switching control signal.

Abstract: A stacked switched resistance device has been developed. The stacked switched resistance device includes a plurality of segments connected in series. Each segment includes a resistor including an inherent parasitic capacitance, and a switch connected in series with the resistor, the switch being configured to connect and disconnect the resistor from the plurality of segments in response to a predetermined clock signal. An effective resistance of the stacked switched resistance device exceeds another effective resistance of at least one resistor with an equivalent inherent resistance that is connected in series to a single switch configured to connect and disconnect the at least one resistor in response to the predetermined clock signal.

Abstract: A communication system includes a demodulator configured to demodulate an amplified modulated signal responsive to a first carrier signal. The demodulator includes a filter and a gain adjusting circuit. The filter is configured to generate a filtered first signal based on a first signal. The first signal is based on the first carrier signal and the amplified modulated signal. The filter has a gain adjusted based on a set of control signals. The gain adjusting circuit is coupled to the filter, and configured to generate the set of control signals based on at least a voltage of the filtered first signal or a voltage of a second signal. The gain adjusting circuit includes a first peak detector configured to output a peak value of the voltage of the second signal. The voltage of the second signal includes a voltage of the first signal or a voltage of a reference signal.

Abstract: An “all-digital” operational amplifier architecture, that does not have the constraint of maintaining devices in their saturation region, can leverage the high speed achievable by deeply scaled technology to replace traditional linear current referenced continuous-time operational amplifier circuits with CMOS-like dynamic circuits that require no referencing structure, have no static power consumption, and are compatible with ultra-low supply voltages. Techniques are described to replace analog continuous-time linear operational amplifier input and output stages by a discrete-time comparator circuit, e.g., CMOS-style, and a switched capacitor charge pump circuit, respectively.

Abstract: A peak detector circuit includes a first capacitor coupled to an inverter and a first switch in parallel with the inverter. An input of the inverter couples to second and third switches. The second switch couples to an input voltage node. The third switch couples to an output voltage node of the peak detector circuit. The peak detector circuit includes a second capacitor coupled to the third switch and a third capacitor coupled to the second capacitor by way of a fourth switch. The third capacitor couples via a fifth switch to a power supply voltage node or a ground. A periodic control signal causes the first, second, and third switches to repeatedly open and close and a second control signal causes the fourth and fifth switches to open and close to adjust an output voltage on the output voltage node towards an input voltage on the input voltage node.

Abstract: A delay circuit and an ultrasonic imaging apparatus with the higher-accuracy delay time, the longer maximum delay time, and the lower power consumption are provided. An input line to which an analog input signal is input, a plurality of analog signal memory devices, an output line, a plurality of sampling switches that control connection/disconnection between the input line and the plurality of analog signal memory devices, a plurality of output switches that control connection/disconnection between the plurality of analog signal memory devices and the output line, and a clock generation part that generates sampling switch control signals for controlling the sampling switches and output switch control signals for controlling the output switches are provided, and phase of the sampling switch control signals may be shifted with respect to phase of the output switch control signals.

Abstract: SSC energy buffer circuit includes a switching network and a plurality of energy storage capacitors. The switching network may operate at a relatively low switching frequency and can take advantage of soft charging of the energy storage capacitors to reduce loss. Efficiency of the SSC energy buffer circuit can be extremely high compared with the efficiency of other energy buffer circuits. The SSC energy buffer architecture exhibits losses that scale with the amount of energy buffered, such that a relatively high efficiency can be achieved across a desired operating range. Improvements in SSC energy buffer circuits include, in various implementations, the use of ground reference gate drive, the elimination of a separate precharge circuit through control of at least a portion of the switches of the SSC energy buffer circuit, and/or optimized ratio of capacitance values of two or more capacitors in an SSC energy buffer circuit.

Abstract: A switched capacitor low-pass filter. The filter includes a plurality of switched capacitors, and a plurality of resistors. The resistors increase the slope of the roll-off of the filter, reduce DC gain variations across corners, and minimize the frequency variation across corners. In some embodiments, the clock signal used to control the switched capacitor filters has a duty cycle differing from 50%, to improve the frequency response of the filter.

Abstract: Various embodiments include approaches for predicting unity gain frequency in a MOSFET. In some cases, a method includes predicting a unity gain frequency (fT) in a MOSFET device in a manufacturing line, the method including: measuring a first set of in-line direct current (DC) parameters of the MOSFET on the manufacturing line at a first drain voltage (Vd1); extracting a transconductance (Gm) from the first set of in-line DC parameters as a function of a gate-voltage (Vg) and the first drain-voltage (Vd1); measuring a second set of in-line DC parameters of the MOSFET on the manufacturing line at a second drain voltage (Vd2); extracting a total gate capacitance (Cgg) from the second set of in-line DC parameters as a function of the gate-voltage (Vg); and predicting the unity gain frequency (fT) of the MOSFET based upon the extracted transconductance (Gm) and the extracted total gate capacitance (Cgg).

Abstract: A switched-capacitor voltage divider is provided that functions to divide an input voltage only while a low-duty-cycle clock pulse signal is asserted. All the switches in the switched-capacitor voltage divider are idle during an off time for the low-duty-cycle clock pulse signal.

Abstract: Certain aspects of the present disclosure provide N-path filters with wider passbands and steeper rejection than conventional N-path filters with only a single pole in each filter path. These N-path filters also have a flatter passband with decreased passband droop. One example N-path filter generally includes a plurality of branches selectively connected with a common node, each branch of the N-path filter comprising a switch connected in series with an impedance comprising a common drain amplifier circuit. In certain aspects, the amplifier circuit may include a degeneration circuit for stability and/or a poly-phase feedback circuit to reduce in-band peaking.

Abstract: Technologies are described to DC-couple an integrated amplifier system to a source that provides a signal with an unknown DC component, for example to DC-couple an integrated audio codec to an analog microphone. In one aspect, methods include receiving, by an amplifier, a signal having an unknown DC component, and issuing an amplified signal; low pass filtering, with respect to a cutoff frequency, by a feedback circuit coupled between an output of the amplifier and an input of the amplifier, the amplified signal issued at the output of the amplifier to generate a filtered signal having frequencies lower than the cutoff frequency; and injecting, by the feedback circuit, the filtered signal into the input of the amplifier to cancel the unknown DC component below the cutoff frequency.

Abstract: Various embodiments include approaches for predicting unity gain frequency in a MOSFET. In some cases, a method includes predicting a unity gain frequency (fT) in a MOSFET device in a manufacturing line, the method including: measuring a first set of in-line direct current (DC) parameters of the MOSFET on the manufacturing line at a first drain voltage (Vd1); extracting a transconductance (Gm) from the first set of in-line DC parameters as a function of a gate-voltage (Vg) and the first drain-voltage (Vd1); measuring a second set of in-line DC parameters of the MOSFET on the manufacturing line at a second drain voltage (Vd2); extracting a total gate capacitance (Cgg) from the second set of in-line DC parameters as a function of the gate-voltage (Vg); and predicting the unity gain frequency (fT) of the MOSFET based upon the extracted transconductance (Gm) and the extracted total gate capacitance (Cgg).

Abstract: An approach to time domain filtering uses a passive charge sharing approach to implement an infinite impulse response filter. Delayed samples of an input signal are stored as charges on capacitors of a first array of capacitors, and delayed samples of the output signal are stored as charges on capacitors of a second array of capacitors. Outputs are determined by passively coupling capacitors of the first and second arrays to one another, and determining the output according to a total charge on the coupled capacitors. In some examples, a gain is applied to the total charge prior to storing the output on the second array of capacitors. In some examples, a charge scaling circuit is applied to the charges stored on the arrays prior to coupling capacitors to form the output.

Abstract: A power supply efficiently suppresses transient voltages by storing the maximum charge expected in the transient and releasing it during the transient event at a rate in an equal but opposite amount to the transient, preventing the battery voltage from collapsing. The described power supply provides improved efficiency compared to conventional architectures for transient suppression, thus increasing the length of time between battery charges and creating a better user experience.

Abstract: A circuit can include an NMOS transistor having a drain and a source, a p-well containing the drain and the source, an n-well under the p-well, a circuit node, and a connection element connecting the n-well to the circuit node. The connection element can include a diode having an anode terminal connected to the circuit node and a cathode terminal connected to the n-well, a resistor having a first terminal connected to the circuit node and a second terminal connected to the n-well, a conductor directly connecting the n-well to the circuit node, or a well switch configured to connect the n-well to the circuit node during an enable phase of a switching signal and to electrically float the n-well during a non-enable phase of the switching signal. The diode can include a diode-connected transistor. The circuit node can be configured to receive a predetermined voltage having a magnitude equal to or greater than an upper supply voltage.

Abstract: A common-mode feedback module is disclosed for controlling feedback in an amplifier, such as a multi-stage amplifier. The common-mode feedback module may include a feedback input stage, a cascode stage, and a feedback output stage. The common-mode feedback module may provide feedback, such as negative feedback to the amplifier to extend a bandwidth of a frequency response and/or increase stability.

Abstract: Amplifier circuits implemented with a buffer amplifier with a voltage gain substantially equal to one. In one example, a continuous-time amplifier is implemented by applying the input source across the input and the output terminals of the buffer amplifier. In another example, a discrete-time amplifier is implemented. During the sampling phase at least one input voltage is sampled, and during the transfer phase at least one capacitor is coupled across the input and the output terminals of a buffer amplifier to effectuate an amplification.

Abstract: A signal processing device has a first discrete time analog signal processing section, which has an input, an output, a plurality of charge storage elements, and plurality of switch elements coupling the charge storage elements. The device has a controller coupled to the first signal processing section configured to couple different subsets of the charge elements of the first signal processing section in successive operating phases to apply a signal processing function to an analog signal presented at the input of the first signal processing section and provide a result of the applying of the signal processing function as an analog signal to the output of first signal processing section. The signal processing function of the first signal processing section comprises a combination of a filtering function operating at a first sampling rate and one or more modulation functions operating at corresponding modulation rates lower than the first sampling rate.

Abstract: A charge-domain filter (CDF) apparatus and an operation method thereof are provided. The CDF apparatus includes an input-signal combination network (ISCN), a switch-capacitor network (SCN) module, an output-signal combination network (OSCN), and a bandwidth compensation network (BCN). The input terminal of the ISCN receives an input signal. The SCN module is connected between the ISCN and the OSCN. The OSCN outputs an output signal of the CDF apparatus. The BCN senses the signal of the SCN module, senses the signal of the OSCN, or senses the signal of each of the SCN module and the OSCN, and correspondingly generates a forward signal or a feedback signal for the ISCN or the OSCN according to the sensing result to perform bandwidth compensation.

Abstract: A pseudo-differential accelerometer resistant to EMI is disclosed that includes a device with a sensor core connected to an integrated circuit including a chopper, differential amplifier, and dummy core. The chopper swaps input to output connections during different states. The dummy core is coupled to a dummy chopper input. Three bond wires coupling the sensor output to a sensor chopper input, a first chopper output to a first sensor input, and a second chopper output to a second sensor input can connect the sensor and integrated circuit. The device can include a dummy pad and dummy bond wire connecting the dummy pad to the dummy chopper input. This configuration requires four bond wires connecting the sensor and integrated circuit. A neutralization core can be connected to the sensor chopper input. The chopper can change states to smear noise across a wide range, or away from a band of interest.

Abstract: A sampling circuit is provided that includes a first sampling circuit that shifts a frequency, at which a gain of a frequency characteristic is maximized, to a lower frequency side, and a second sampling circuit that shifts the frequency, at which the gain of the frequency characteristic is maximized, to a higher frequency side. The sampling circuit also includes an output section provided in an output side of the first sampling circuit and an output side of the second sampling circuit, and outputs a sum or a difference between an output from the first sampling circuit and an output from the second sampling circuit.

Abstract: Fixed capacitive circuits are described which perform arithmetical summation operations over sets of scaled analog values, where the constant parameters of the summations and scaling multiplications are formed as ratios of circuit element values. The passive nature of the design can enable efficient integrated circuit implementation.

Abstract: Techniques for reducing noise and power consumption in a loop filter for a phase-locked loop (PLL) are described herein. In one embodiment, a loop filter for a PLL comprises a first proportional capacitor, a second proportional capacitor, an active device, and a plurality of switches. The plurality of switches are configured to alternately couple the first proportional capacitor and the second proportional capacitor to a first charge pump, to alternately couple noise from the active device to the first proportional capacitor and the second proportional capacitor, and to alternately couple the first proportional capacitor and the second proportional capacitor into a feedback circuit, wherein the feedback circuit produces an output voltage of the loop filter.

Abstract: A method and apparatus for use in a digitally tuning a capacitor in an integrated circuit device is described. A Digitally Tuned Capacitor DTC is described which facilitates digitally controlling capacitance applied between a first and second terminal. In some embodiments, the first terminal comprises an RF+ terminal and the second terminal comprises an RF? terminal. In accordance with some embodiments, the DTCs comprise a plurality of sub-circuits ordered in significance from least significant bit (LSB) to most significant bit (MSB) sub-circuits, wherein the plurality of significant bit sub-circuits are coupled together in parallel, and wherein each sub-circuit has a first node coupled to the first RF terminal, and a second node coupled to the second RF terminal. The DTCs further include an input means for receiving a digital control word, wherein the digital control word comprises bits that are similarly ordered in significance from an LSB to an MSB.

Abstract: In a high-performance interface circuit for micro-electromechanical (MEMS) inertial sensors, an excitation signal (used to detect capacitance variation) is used to control the value of an actuation signal bit stream to allow the dynamic range of both actuation and detection paths to be maximized and to prevent folding of high frequency components of the actuation bit stream due to mixing with the excitation signal. In another aspect, the effects of coupling between actuation signals and detection signals may be overcome by performing a disable/reset of at least one of and preferably both of the detection circuitry and the MEMS detection electrodes during actuation signal transitions. In a still further aspect, to get a demodulated signal to have a low DC component, fine phase adjustment may be achieved by configuring filters within the sense and drive paths to have slightly different center frequencies and hence slightly different delays.

Abstract: An integrated continuous-time active-RC filter comprises a set of opamp integrators with Operational Transconductance Amplifiers (OTAs), and at least one assistant transconductor connected between an input and an output of each of the integrators of the set; wherein the assistant transconductor comprises a plurality of sets of MOSFETS connected in parallel to each other wherein each set of MOSFETS is formed by a pair of MOSFETs connected in series, with one MOSFET of the pair operating in the triode region and the other MOSFET of the pair operating in the saturation region; and wherein the assistant transconductor is configured to inject an assistant current into the output of each of the integrators in the set to enhance the linearity and speed of the opamp integrators of the set.

Abstract: A received plurality of signals may be filtered to select an in-band signal and/or an out-of-band. A signal strength of the selected signal(s) may be measured. A resolution of an analog-to-digital converter may be controlled based on the measured signal strength(s). The selected in-band signal may be converted to a digital representation via the analog-to-digital converter. The resolution may be decreased when the strength of the in-band signal is higher, and increased when the strength of the in-band signal is lower. The resolution may be increased when the strength of the out-of-band signal is higher, and decreased when the strength of the out-of-band signal is lower. A signal-to-noise ratio and/or dynamic range of the selected signal(s) may be determined based on the measured signal strength(s), and may be utilized to adjust the resolution of the analog-to-digital converter.

Abstract: Two resistive elements and a capacitive element are coupled between a first node and each of an inverting input terminal of an operational amplifier, an output terminal of the operational amplifier, and a common node. A resistive element and a capacitive element are coupled between the first node and a signal input terminal. Two capacitive elements and a resistive element are coupled between a second node and each of the inverting input terminal, the output terminal, and the common node. Two capacitive elements are coupled between the second node and each of the signal input terminal, and the common node.

Abstract: A noise-removing circuit includes a first capacitor to charge a first voltage supplied to a first node during a first period in which a first switching control signal is supplied, a second capacitor to charge a second voltage supplied to a third node during the first period, a third capacitor to charge the first voltage during a second period in which a second switching control signal is supplied, and to charge the second voltage charged in the second capacitor as a third voltage during a third period in which a third switching control signal is supplied, a fourth capacitor to charge the second voltage during the second period, and to charge the first voltage charged in the first capacitor as a fourth voltage during the third period, and a differential amplifier to output a voltage difference between the third voltage and the fourth voltage.

Abstract: An embodiment integrated circuit includes a first capacitive element including a first metal-oxide-semiconductor (MOS) capacitor and a second capacitive element coupled in parallel with the first capacitive element, where the second capacitive element includes a second MOS capacitor. Also, the integrated circuit includes a third capacitive element coupled in parallel with the first capacitive element and the second capacitive element, where the third capacitive element includes a first metal-insulator-metal (MIM) capacitor and a fourth capacitive element coupled in parallel with the first capacitive element, the second capacitive element, and the third capacitive element, where the fourth capacitive element includes a second MIM capacitor.

Abstract: A circuit that provides a rotating coefficient FIR filter with all necessary coefficient sets present at the same time, without the need for delay elements or devices providing for adjustable impedances is described. An input signal is sampled in round robin fashion by a plurality of sample and hold devices. The outputs of the sample and hold devices are connected to sets of impedance devices. Each set of impedance devices implements the coefficients of the desired frequency response of the filter. The impedance devices in each set are connected to the sample and hold devices in a different order from each other set, so that each set of impedance devices will produce the desired frequency response when a different one of the sampling circuits contains a new sample of the input signal. Switches connect the sets of impedance devices to an output, only one switch being closed at a time to provide the output signal.

Abstract: A loop filter is described. The loop filter has first and second inputs and an output. A loop filter capacitor is coupled to the loop filter output. Sample switches are coupled to the second loop filter input. A voltage divider is coupled to reset switches. Switched capacitors are coupled to sample switches, the reset switches, the loop filter capacitor, and the loop filter output.

Abstract: An oscillator, comprising: a pair of transistors to which source terminals are interconnected and to which drain and gate terminals are coupled by a positive feedback loop comprising an oscillator tank, wherein the source terminals of the transistors are connected to a current source configured to control physical parameters of the oscillator.