Abstract: An approach for a sampling circuit to reduce noise in signals (e.g., as received from photo diodes or the like) is provided. In one embodiment of the present invention, there is a sampling circuit comprising: an amplifier, which amplifies charge signals generated at photo diodes and converts them to voltage signals; the first sample and hold circuit, which samples the voltage signal and charges the first capacitor according to the first switching signal, and outputs the stored charge as a reset signal based on a readout signal; the second sample and hold circuit, which samples the signals and charges the second capacitor according to the second switching signal that is non-overlapping to the first switching signal, and outputs the stored charge as a reset signal based on the readout signal; a resistor that acts as a low-pass filter placed in between the first and the second capacitors' common nodes.

Abstract: Described embodiments provide an interleaved sampler having N sample and hold circuits for sampling an input signal, and M multiplexers. Each multiplexer is adapted to couple all N of the plurality of sample and hold circuits to a respective output of the interleaved sampler. The interleaved sampler samples at a sample rate of fs, has an interleaved sampling period of M/fs, where M is greater than one and less than N. Because there are more sample and hold circuits than there are samples taken during an interleaved sampling period, different combinations of the sample and hold circuits are used from interleaved sample period to interleaved sample period. This reduces spurious tones generated from offset voltages when using interleaved sample and hold circuits. The order of the sample and hold circuits are clocked might be random, pseudorandom, or a fixed pattern longer than the interleaved sampling period.

Abstract: There is disclosed current-mode time-interleaved sampling circuitry configured to be driven by substantially sinusoidal clock signals. Such circuitry may be incorporated in ADC circuitry, for example as integrated circuitry on an IC chip. The disclosed circuitry is capable of calibrating itself without being taken off-line.

Abstract: A zero-crossing detector with effective offset cancellation includes a set of series connected capacitors and an amplifier having an input terminal. An offset capacitor is operatively connected between the amplifier and the set of series connected capacitors. A switch is operatively connected to the input terminal, and an offset sampling capacitor is operatively connected to the switch. The switch connects the offset sampling capacitor to the input terminal of the amplifier during a charge transfer phase.

Abstract: Aspects of the disclosure provide a sampling circuit with reduced sampling distortions. The sampling circuit can include a switch and a first driving module configured to drive a first signal in response to an input signal onto a first channel terminal of the switch. The sampling circuit also can include a bootstrap module coupled to a control terminal of the switch and a second driving module coupled to the bootstrap module. The second driving module can be configured to drive a second signal in response to the input signal to the bootstrap module, such that the bootstrap module can vary a control voltage on the control terminal based on the input signal for turning on the switch and causing an output voltage on a second channel terminal of the switch to track the first signal on the first channel terminal of the switch.

Abstract: The present invention discloses a multi-stage sample and hold (S/H) circuit that includes: a first S/H circuit for sampling a sensing signal of a sensor multiple times and accumulating them into a first sampled signal, and outputting the first sampled signal; and a second S/H circuit for receiving the plurality of first sampled signals and accumulating them into a second sampled signal. As a result, when one or more first sampled signals are saturated due to instantaneous noise, the second sampled signal is not saturated, thereby increasing the noise tolerance of the multi-stage S/H circuit.

Abstract: The present invention provides a circuit for concurrent integration of multiple differential signals. The circuit comprises a plurality of Stage 1 integration circuits arranged in an array and a plurality of Stage 2 integration circuits arranged in an array. Each of the Stage 1 integration circuits is configured to concurrently integrate an input signal, and to send out a Stage 1 positive signal and a Stage 1 negative signal that is reverse to the Stage 1 positive signal. Each of the Stage 2 integration circuits is configured to integrate a differential signal from a Stage 1 positive signal sent from a corresponding Stage 1 integration circuit and a Stage 1 negative signal sent from another Stage 1 integration circuit next to the corresponding Stage 1 integration circuit to output a Stage 2 signal.

Abstract: A method for generating a signal is provided, the method including: providing a first signal having a first signal frequency; providing a second signal having a second signal frequency or a third signal frequency, wherein the second signal frequency is higher than the third signal frequency; switching the second signal having the second signal frequency to the third signal frequency based on a predefined first signal event of the first signal; and returning the second signal having the third signal frequency to the second signal frequency in response to a predefined second signal event.

Abstract: A sample and hold circuit is provided. The circuit includes a plurality of switches, a first capacitor, an operational amplifier having a first input selectively coupled to the first capacitor and an output, a second capacitor and a third capacitor both selectively coupled to the first capacitor and both selectively coupled between the first input of the operational amplifier and the output of the operational amplifier, wherein the plurality of switches are configured to receive a plurality of control signals such that the first capacitor is configured to sample an input signal in a sample phase and to transfer a charge to one of the second capacitor and the third capacitor in a hold phase, and the second capacitor and third capacitor are configured to alternate between holding the transferred charge and resetting in any back-to-back hold phases.

Abstract: A switch may include a MOS transistor alternatively operating in an ON phase and an OFF phase, a first voltage level shifter, and a second voltage level shifter. The MOS transistor may include a source for receiving an input signal, a drain for connecting to a load, and a gate. The first voltage level shifter may be selectively coupled between the source and the gate during the ON phase, and the second voltage level shifter may be selectively coupled between the gate and the source during the OFF phase.

Abstract: Sample-and-hold circuits typically operate at maximum speed when the sampling phase is much shorter than the holding phase. Thus, a device driving the sampling capacitor is disconnected most of the time. Methods and apparatus use the holding phase to store the full charge required by the sampling capacitor to track the amplifier output in at least two “boost” capacitors configured such that when the sampling capacitor is switched to the driver, the boost capacitors are also switched to the driver. Thus, the sampling capacitor is almost instantly charged to the required voltage, and the driver needs to supply only any remaining “error” charge, avoiding delays due to driver output slewing.

Abstract: The organic light emitting display device according to the present invention includes a scan driver for supplying a scan signal to scan lines during a frame time-divided into a plurality of subframes, a data driver coupled to output lines for supplying data signals on each of the output lines, data distributors coupled to the output lines for distributing the data signals to data lines, concurrently, in synchronization with the scan signal, and pixels located at crossing regions of the data lines and the scan lines. Each of the data distributors includes a sampling latch for distributing the data signals to different channels and for storing the data signals, and a holding latch coupled to the sampling latch for supplying the data signals of the channels to the data lines concurrently.

Abstract: Aspects of the disclosure provide a sampling circuit having reduced sampling distortions. The sampling circuit can include a switch having a control terminal, a first channel terminal and a second channel terminal. The first channel terminal can be configured to receive an input signal, and the control terminal can be configured to have a control voltage that varies with regard to the input signal, such that a conducting channel can be formed between the first channel terminal and the second channel terminal to enable an output voltage on the second channel terminal to track the input signal. Further, the sampling circuit can include a bootstrap module coupled to the control terminal of the switch. The bootstrap module can be configured to change the control voltage by a substantially constant value to turn off the conducting channel between the first channel terminal and the second channel terminal in order to hold the output voltage as a sample of the input signal.

Abstract: An operational circuit includes: a gain control circuit arranged to provide a gain value upon an input signal according to a set of control signals, wherein the gain control circuit includes a first resistor-based network and a second resistor-based network; an operational amplifier coupled to the gain control circuit and arranged to generate an output signal according to the input signal and the gain value; and a first capacitor coupled to the operational amplifier and arranged to hold the output signal between a first input terminal and a first output terminal of the operational amplifier, wherein when the operational circuit is operating, a first terminal of the first capacitor is consistently coupled to the first input terminal of the operational amplifier, and a second terminal of the first capacitor is consistently coupled to the first output terminal of the operational amplifier.

Abstract: A sample and hold circuit is provided. The circuit includes a plurality of switches, a first capacitor, an operational amplifier having a first input selectively coupled to the first capacitor and an output, a second capacitor and a third capacitor both selectively coupled to the first capacitor and both selectively coupled between the first input of the operational amplifier and the output of the operational amplifier, wherein the plurality of switches are configured to receive a plurality of control signals such that the first capacitor is configured to sample an input signal in a sample phase and to transfer a charge to one of the second capacitor and the third capacitor in a hold phase, and the second capacitor and third capacitor are configured to alternate between holding the transferred charge and resetting in any back-to-back hold phases.

Abstract: An interpolation circuit includes: a first node to receive a first current; a second node to receive a second current; a third node to receive a third current; a first capacitor circuit including: first capacitors; a first switch to couple one end of each of first capacitors to one of first and second nodes; and a first output coupled to the other end of each of first capacitors; a second capacitor circuit including: second capacitors; a second switch to couple one end of each of second capacitors to one of second and third nodes; and a second output node coupled to the other end of each of second capacitors; and a third capacitor circuit including: a third capacitor whose one end is coupled to the second node; and a third switch to couple the other end of the third capacitor to one of first and second output nodes.

Abstract: A sampling circuit and a receiver, with relatively simple configurations, and clocks, exhibiting excellent frequency characteristics, are provided. In discrete time circuits, a charging switch is controlled on and off using one of four-phase control signals. A rotate capacitor shares electrical charge accumulated in an IQ generating circuit via the charging switch. A dump switch is controlled on and off using a different signal from the control signal used to control the charging switch on and off, among the four-phase control signals. A buffer capacitor shares electrical charge with the rotate capacitor via the dump switch to form an output value.

Abstract: A packaged controller for closed-loop control applications includes two dies packaged together in a semiconductor package. The first die is optimized for digital circuitry and includes a processor, an ADC, a serial bus interface, and a sequencer. The second die is optimized for analog circuitry and includes a serial bus interface, a plurality of sample/hold circuits, and an analog multiplexer. The sequencer on the first die causes a series of multi-bit values to be communicated serially across a low latency serial bus to the second die, and thereby controls the analog multiplexer and the asserting of a sample/hold signal on the second die. Under control of the sequencer, multiple voltages are captured simultaneously on the second die, and then are multiplexed one by one to the ADC on the first die for conversion into digital values. The architecture reduces complexity and cost of the overall packaged controller.

Abstract: A high side controller capable of sensing input voltage and output voltage of a power conversion circuit, including: a first switch, having a control end and two channel ends, the control end being coupled to a gate signal, and one of the two channel ends being coupled to a voltage signal, wherein the voltage signal is proportional to a negative version of the input voltage when the gate signal is active; an inverting amplification circuit, having an input end coupled to the other one of the two channel ends, and an output end for providing a first processed voltage; and a first sample and hold circuit, having a control input end coupled to the gate signal, an input end coupled to the first processed voltage, and an output end for providing a first sample voltage.

Abstract: Systems and methods for compressing high-frequency signals are described in certain embodiments herein. According to certain embodiments, a high-frequency signal can be converted into a lower frequency signal so that it can be processed by one or more devices in a lower frequency infrastructure. In certain embodiments, the high-frequency signal can be compressed by certain signal conditioning components and an algorithm executed by a computer processor to at least receive a high-frequency signal, correct the high-frequency signal, determine a number of samples to be taken from the high-frequency signal (i.e., sample the high-frequency signal), store a value associated with the sampled signal, and generate a waveform that includes lower frequency content that may represent the original, high-frequency signal.

Abstract: In one embodiment, a bootstrap switch circuit has (i) a switch device that selectively provides a input signal as an output signal and bootstrap circuitry that provides a relatively high-voltage control signal to the gate of the switch device to turn on the switch device while preventing any over-voltage conditions from being applied to the switch device. The bootstrap circuitry includes a capacitor and a number of transistors configured as either switches or inverters. The circuit has two operating phases: one in which the capacitor gets charged while the switch device is turned off and the other in which the charged capacitor is isolated and used to generate the high-voltage control signal to be a fixed voltage difference above the current voltage level of the input signal applied to the switch device, thereby preventing an over-voltage condition.

Abstract: A time-interleaved sample-and-hold system includes a first sample-and-hold circuit and a second sample-and-hold circuit. The first sample-and-hold circuit and the second sample-and-hold circuit share a common sampling switch. A method of remediating a timing offset between a first sample-and-hold circuit and a second sample-and-hold circuit in a time-interleaved sample-and-hold system includes switching at least one shunt capacitor disposed between two logic gates in a timing circuit to adjust a delay between a timing signal for a common sampling switch electrically coupled to the first and second sample-and-hold circuits and a timing signal for at least one of the sample-and-hold circuits.

Abstract: A sample-and-hold circuit connected to an analog-to-digital converter (ADC) is provided. The sample-and-hold circuit includes an operational amplifier configured to output a result signal to the ADC; a feedback capacitor connected between an input terminal and an output terminal of the operational amplifier to form a feedback path; a plurality of sampling capacitor blocks each connected to one of a plurality of channels. The plurality of sampling capacitor blocks configured to sample and hold an analog signal input to each of the channels; a plurality of controllers each connected between one of the sampling capacitor blocks and the operational amplifier.

Abstract: A comparator based circuit with effective offset cancellation includes first and second amplifiers and an offset capacitor operatively connected to the first and second amplifiers. An offset voltage source generates an offset voltage. A first switch connects the offset voltage source to ground during a first time period. The first amplifier generates an output voltage in response to the first switch connecting the offset voltage source to ground during the first time period. A second switch connects the offset capacitor to ground during a second time period. The first switch disconnects the offset voltage source from ground during a third time period, and the second switch disconnects the offset capacitor from ground during the third time period.

Abstract: An architecture of an integrated circuit allows for the canceling of noise sampled on a capacitor in the integrated circuit, after an input signal has already been sampled. Thermal noise correlated with an arbitrary input signal may be canceled after selectively controlling a plurality of switching devices during a sequence of clock phases. An auxiliary capacitor may be used to store a voltage equal to the thermal noise and enable the cancellation of the thermal noise from the sampled signal in conjunction with a noise cancellation unit.

Abstract: A switch circuit is described, where a switch to be controlled is formed of two NMOS transistors having their source terminals connected together and their gate terminals connected together. Their drain terminals are the input and output terminals of the switch. A driver circuit controls a bootstrap circuit that is formed of a latching circuit and a capacitor. When the switch is in an off state, the driver circuit connects the capacitor to a charging voltage source for charging the capacitor to a bootstrap voltage, and applies a non-zero voltage across the latching circuit. When the driver circuit is controlled to turn on the switch, the driver circuit disconnects the capacitor from the charging voltage source, and the latching circuit becomes conductive and effectively connects the capacitor across the gate and source terminals of the switch to turn it on with the bootstrap voltage. The bootstrap voltage across the capacitor maintains the latching circuit in a latched conductive state.

Abstract: A circuit for preventing a setup fail between a first latch and a second latch according to one embodiment of the present invention comprises a mimic combinational logic module and a clock compare module. The mimic combinational logic module is configured to receive a first clock signal for the first latch and to generate a delayed first clock signal, which is a delayed version of the first clock signal. The clock compare module is configured to provide a delayed second clock signal, which is a delayed version of a second clock signal for the second latch, to the second latch after receiving the delayed first clock signal and the second clock signal.

Abstract: A sample and hold circuit that is provided with an input stage amplifier circuit for amplifying an input signal and a hold circuit for holding an output signal of the input stage amplifier circuit, with a sampling clock signal as a trigger, is further provided with a hold circuit bias current switching circuit for switching a bias current of the hold circuit to a first separate circuit that is functionally independent of the sample and hold circuit, in a case where the hold circuit is in a hold period, to supply the bias current to the circuit.

Abstract: A time-interleaved track-and-hold circuit includes a clock generator adapted to receive a global sine-wave clock signal and to generate therefrom multiple square-wave output clock signals of different phases. The track-and-hold circuit includes a switching array operative in at least a track mode or a hold mode. The switching array includes multiple switch circuits, each switch circuit adapted to receive an analog input signal, a corresponding one of the output clock signals, and the global sine-wave clock signal. Each switch circuit is operative to utilize the corresponding one of the output clock signals during the track mode for tracking the analog input signal, and is operative during the hold mode to store the input signal sampled during the track mode as an output of the switch circuit and to utilize the global sine-wave clock signal during the hold mode for synchronizing sampling instants of the respective outputs of the switch circuits.

Abstract: Various embodiments of this disclosure may describe a two-stage ADC circuit, and a time-interleaved system based on the two-stage ADC circuit. The two-stage ADC circuit may include a SAR converter for the first stage and a charge based TDC for the second stage. The two-stage ADC circuit may be used in high performance serial I/O applications. Other embodiments may be disclosed and claimed.

Abstract: A packaged controller for closed-loop control applications includes two dice packaged together in a semiconductor package. The first die is optimized for digital circuitry and includes a processor, an ADC, a serial bus interface, and a sequencer. The second die is optimized for analog circuitry and includes a serial bus interface, a plurality of sample/hold circuits, and an analog multiplexer. The sequencer on the first die causes a series of multi-bit values to be communicated serially across a low latency serial bus to the second die, and thereby controls the analog multiplexer and the asserting of a sample/hold signal on the second die. Under control of the sequencer, multiple voltages are captured simultaneously on the second die, and then are multiplexed one by one to the ADC on the first die for conversion into digital values. The architecture reduces complexity and cost of the overall packaged controller.

Abstract: A positive/negative sampling and holding (S/H) circuit is disclosed herein. The positive/negative S/H circuit includes an operational amplifier, a first capacitor, a second capacitor being parallel with the first capacitor and forming an integration circuit with the operational amplifier, and several discharge switches correspondingly connecting discharge paths of the first and the second capacitors to control the first and the second capacitors to output a first sampling signal and a second sampling signal respectively, and herein, the first and the second sampling signals has the same magnitude but opposite voltage polarities.

Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits and embodiments such as operational transconductance amplifiers, biasing circuits, integrators, continuous-time sigma delta modulators, track-and-hold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.

Abstract: A switched capacitor circuit includes a threshold detector to generate a threshold detection signal when a difference between first and second input signals crosses a predetermined level. A coarse current source produces a coarse ramp. A series sampling capacitor samples a coarse output voltage when the threshold detector indicates a first threshold crossing. The sampling capacitor is connected in series with a fine current source producing a fine ramp.

Abstract: In one embodiment, a comparator of a Flash analog-to-digital converter (ADC) is calibrated in the background by switching the comparator to a feedback loop, determining the comparator's current reference level, and adjusting the comparator's reference level to a target reference level by charging a reference capacitor coupled the comparator.

Abstract: Circuits and methods for sampling differential input signals having wide input swings including voltages below ground potential, and capable of operating on a single positive supply voltage are disclosed. In an embodiment, the circuit includes a first input switch circuit and a second input switch circuit, a sample and hold circuitry and an operational amplifier. Each of the first and second input switch circuits includes serially connected PMOS switch and NMOS switch for receiving a differential input signal. The sample and hold circuitry includes a first sampling capacitor, a second sampling capacitor and a plurality of switches. The switches are configured to provide the differential input signal to the sampling capacitors for the sampling in a sample phase, and are configured to provide the sampled differential input signal at an output of the operational amplifier in a hold phase.

Abstract: Provided is an electronic circuit system which facilitates skew timing adjustment while preventing increase of power consumption. An electronic circuit system includes: a track hold circuit module formed by a hierarchical tree structure of track hold circuits which can track-hold an analog value of an analog signal; and a control signal generation module which supplies an operation control signal to each of the track hold circuits in the hierarchical tree structure. In the hierarchical tree structure, the number of track hold circuits of each of the hierarchies is stepwise changed from the first hierarchy of the input side to which an analog signal is inputted, toward the final hierarchy of the final output side as the number of hierarchies is increased.

Abstract: A comparator-based buffer method and system enhance the driving capability of high-gain amplifiers with switched-capacitor loads. It includes a current source, a comparator, switches, sampling capacitor and overshoot correction resistor. A correction solution using a resistor in the charging path and a correction phase reduces the overshoot of the output voltage while constraining power consumption and minimizing components. Spectre® simulations verify the effectiveness of the invention.

Abstract: The present invention is related to a sample and hold circuit and an A/D converter, and prevents an output saturation for an input voltage over a power supply voltage range in the sample and hold circuit. A first switch which is turned on when an input voltage is to be sampled; a sampling capacitor configured to sample the input voltage input via the first switch when the first switch is turned on, and sample a predetermined reference voltage when the first switch is turned off; an adding/subtracting part configured to perform an addition or a subtraction between the input voltage sampled by the sampling capacitor and the predetermined reference voltage sampled by the sampling capacitor; and a hold part configured to hold and output a voltage obtained by the addition or the subtraction by the adding/subtracting part are provided.

Abstract: A track-and-hold circuit is provided. This track-and-hold circuit is adapted to track an analog input signal and hold a sampled voltage of the analog input signal at a sampling instant for processing by other circuitry, in response to a track signal that alternates with a hold signal. Preferably, the track-and-hold circuit includes a bi-directional current source that sources and sinks current through a first output node and a second output node, a unity gain amplifier that is coupled to first and second output nodes of the bi-directional current source and that receives the analog input signal, a resistor coupled to an output of the unity gain amplifier, and a capacitor coupled between the resistor and ground. Of interest, however, is the bi-directional current source, which includes a differential input circuit that is adapted to receive the track signal and the hold signal and that is coupled to the first and second output nodes and an RC network that is coupled to the differential input circuit.

Abstract: A sample and hold circuit includes an operational amplifier; a sampling capacitor configured to sample input voltages at a plurality of different timings; an adding/subtracting unit configured to perform an adding or subtracting operation of the input voltages sampled by the sampling capacitor; and an offset voltage removing unit configured to remove an input offset voltage component of the operational amplifier from a voltage obtained by the adding or subtracting operation. The operational amplifier is configured to produce an output by holding the voltage from which the input offset voltage component of the operational amplifier has been removed by the offset voltage removing unit.

Abstract: A sampling circuit can include a switch having a control terminal, a first channel terminal and a second channel terminal. The first channel terminal can be configured to receive an input signal, and the control terminal can be configured to have a control voltage that varies with regard to the input signal, such that a conducting channel can be formed between the first channel terminal and the second channel terminal to enable an output voltage on the second channel terminal to track the input signal. Further, the sampling circuit can include a bootstrap module coupled to the control terminal of the switch. The bootstrap module can be configured to change the control voltage by a substantially constant value to turn off the conducting channel between the first channel terminal and the second channel terminal in order to hold the output voltage as a sample of the input signal.

Abstract: A track and hold circuit that includes a switch device and a capacitive hold device. The track and hold circuit includes a track-voltage generating device adapted to generate a control voltage based on a signal on an input terminal of the switch device and supply the control voltage to the switch device during track phases of the track and hold circuit. The control voltage provides a channel charge, which is the same for each track phase, in the switch device.

Abstract: A circuit comprising an input, two or more sampling capacitors, means for connecting each sampling capacitor to said input, means for discharging the sampling capacitors to a given voltage in a reset phase, means to use the voltage across the sampling capacitor for further processing in a hold phase, operating the two sampling capacitors in anti-phase such that the reset phase and sampling phase of one channel are performed in the time period the other channel is in hold phase.

Abstract: Circuits and methods that improve the performance of electronic sampling systems are provided. Impedances associated with sampling semiconductor switches are maintained substantially constant during sample states, at least in part, by compensating for encountered input signal variations in order to reduce or minimize signal distortion associated with sampled signals that pass through the sampling switch.

Abstract: Circuits and methods that improve the performance of electronic sampling systems are provided. Impedances associated with sampling semiconductor switches are maintained substantially constant during sample states, at least in part, by compensating for encountered input signal variations in order to reduce or minimize signal distortion associated with sampled signals that pass through the sampling switch.

Abstract: In conventional analog-to-digital converter (ADC) systems, jitter can be a problem because of delay circuits within the sample signal path. Here, an ADC system is provided with a modified delay locked loop (DLL), namely having a variable delay and a fixed delay. The modification to the delay line of DLL enables the removal of delay circuits from the sample path, improve the overall signal to noise ration (SNR).

Abstract: A track and hold circuit that includes a switch device and a capacitive hold device. The track and hold circuit includes a track-voltage generating device adapted to generate a control voltage based on a signal on an input terminal of the switch device and supply the control voltage to the switch device during track phases of the track and hold circuit. The control voltage provides a channel charge, which is the same for each track phase, in the switch device.

Abstract: According to a spurious pulse generator of this invention, integrating circuits are provided at a plurality of stages for carrying out integrating operations about time and outputting a spurious pulse, the integrating circuits being constructed to input a voltage value for controlling a crest value which is a peak swing of the spurious pulse to an amplifier forming an integrating circuit at a most upstream stage when a switching element is ON, and to input a constant voltage value when the switching element is OFF. As a result, the voltage value before ON-state and after ON-state of the switching element does not change but remains a constant voltage value, thereby obtaining a desired spurious pulse.

Abstract: A track-and-hold circuit is provided. This track-and-hold circuit is adapted to track an analog input signal and hold a sampled voltage of the analog input signal at a sampling instant for processing by other circuitry, in response to a track signal that alternates with a hold signal. Preferably, the track-and-hold circuit includes a bi-directional current source that sources and sinks current through a first output node and a second output node, a unity gain amplifier that is coupled to first and second output nodes of the bi-directional current source and that receives the analog input signal, a resistor coupled to an output of the unity gain amplifier, and a capacitor coupled between the resistor and ground. Of interest, however, is the bi-directional current source, which includes a differential input circuit that is adapted to receive the track signal and the hold signal and that is coupled to the first and second output nodes and an RC network that is coupled to the differential input circuit.