Abstract: Systems and methods for generating a radio frequency (RF) signal by a digital-to-analog converter (DAC) with transmission frequency within a wide transmission frequency range are described. An output reactance of the DAC coupled (directly or indirectly) to one or more antennas corresponds to the transmission frequency of the RF signals. Multiple embodiments of the DAC are described to include circuitry for tuning the output reactance of the DAC, and therefore, shifting a center frequency to select a transmission frequency range (from multiple transmission frequency ranges) for providing the RF signals.

Abstract: According to one embodiment, a signal processing circuit includes a first voltage setting circuit that sets a reference voltage on an input side of an isolator, a variable gain amplifier circuit that amplifies an output signal of the isolator, a DC offset adjustment circuit that adjusts an offset of the variable gain amplifier circuit, a second voltage setting circuit that sets a reference voltage on an output side of the isolator, and a control circuit that controls the DC offset adjustment circuit in response to a result of comparison of an output voltage of the variable gain amplifier circuit with an output voltage of the second voltage setting circuit.

Abstract: Plasma processing systems and power delivery methods are disclosed. A system may comprise at least one modulating supply that modulates plasma properties where the modulation of the plasma properties has a repetition period, T. Electrical characteristics of an output of the modulating supply are monitored and provided to a controller where the electrical characteristics are analyzed. Characteristics of a waveform with the repetition period T are communicated to at least one piece of equipment connected to plasma processing system to enable synchronization of pieces of equipment connected to the plasma processing system. And in addition, instructions are relayed to the modulating supply and a match network, based on the analyzing of the electrical characteristics, enabling simultaneous tuning of the modulating supply and the match network.

Abstract: An amplifier circuit configuration capable of processing non-contiguous intra-band carrier aggregate (CA) signals using amplifiers is disclosed herein. In some cases, each of a plurality of amplifiers is an amplifier configured as a cascode (i.e., a two-stage amplifier having two transistors, the first configured as a “common source” input transistor, e.g., input field effect transistor (FET), and the second configured in a “common gate” configuration as a cascode output transistor, (e.g. cascode output FET). In other embodiments, the amplifier may have additional transistors (i.e., more than two stages and/or stacked transistors). The amplifier circuit configuration can be operated in either single mode or split mode. A switchable coupling is placed between the drain of the input FETs of each amplifier within the amplifier circuit configuration.

Abstract: A complementary envelope detector contemplates using two pair of mirrored transistors to provide a differential output envelope signal to an associated envelope tracking integrated circuit (ETIC) that supplies control voltages to an array of power amplifiers. While bipolar junction transistors (BJTs) may be used, other exemplary aspects use field effect transistors (FETs). In an exemplary aspect, a first pair are negative channel FETs (nFETs) and a second pair are positive channel FETs (pFETs).

Abstract: This application provides an operational amplifier and a start-up circuit of the operational amplifier. The start-up circuit has the advantages of having a simple structure and consuming less. The operational amplifier includes a multi-stage amplifier and a start-up circuit, where the start-up circuit includes a first start-up transistor and a second start-up transistor. A source of the first start-up transistor and a source of the second start-up transistor are connected to a tail bias node of a first-stage amplifier in the multi-stage amplifier, a gate of the first start-up transistor and a gate of the second start-up transistor are configured to connect to a first bias voltage Vb, and a drain of the first start-up transistor and a drain of the second start-up transistor are connected to input terminals of a second-stage or higher-stage amplifier.

Abstract: An apparatus includes an amplifier. The amplifier has two inputs, and an output. The amplifier has a pole in its transfer function. The frequency of the pole depends on the output current of the amplifier. The amplifier further includes a pole frequency tracking (PFT) circuit. The PFT circuit includes a source follower circuit.

Abstract: An output amplifier which includes a drive voltage generating unit that generates a positive drive voltage and a negative drive voltage corresponding to a difference between an input voltage and an output voltage, an output unit including a first transistor and a second transistor forming a complementary output between a positive power supply terminal and a negative power supply terminal, the first transistor flowing out the current from the positive power supply terminal to the output terminal corresponding to the positive drive voltage, and the second transistor flowing the current from the output terminal into the negative power supply terminal corresponding to the negative drive voltage, and clamp voltage generating circuits that apply a positive clamp voltage corresponding to the input voltage to the positive power supply terminal and apply a negative clamp voltage corresponding to the input voltage to the negative power supply terminal.

Abstract: A phase interpolator with a DAC outputting a first and second value responsive to a control code. A first current mirror generates a first current proportional to the first value. A second current mirror generates a second current proportional to the second value. A first FET pair comprising a first and second FET such that the source terminals of the first FET and the second FET are electrically connected and connect to the first current mirror. A second FET pair comprising a third and fourth FET such that the source terminals of the third FET and the fourth FET are electrically connected and connect to the second current mirror. A first terminal outputs a phase adjusted clock signal as compared to the clock signal, from the first FET and the third FET. A second terminal outputs an inverted phase adjusted clock signal, from the second FET and the fourth FET.

Abstract: An apparatus includes an amplifier circuit including a first transistor and a second transistor. The first transistor may include a gate having a gate oxide with a first thickness and a first gate length. The second transistor may include a gate having a gate oxide with a second thickness and a second gate length. The first transistor and the second transistor may be connected in a cascode configuration and the second thickness and the second gate length are greater than the first thickness and the first gate length, respectively.

Abstract: A differential feedback circuit with an active noise cancelation technique using a dual input differential pair. In the differential feedback circuit, a feedback voltage and a reference voltage connect to a primary input pair. Sensed noise at the inputs is put to a secondary input pair of the differential amplifier, which is inverted with respect to the primary input pair. In other words, the reference voltage, which may be subject to noise, connects directly to one terminal of the secondary input pair and through a low-pass filter to another terminal of the secondary input pair so that the noise, which may be coupled to the differential feedback circuit, cancels at the output of the differential feedback circuit.

Abstract: A power supply circuit and techniques for voltage regulation are described. Certain aspects provide a method of supplying power by a power supply circuit. The method generally includes: generating an output voltage based on a voltage at a Vin node via a first transistor having a gate coupled to a gate of a second transistor, wherein a source of the second transistor is coupled to the Vin node and wherein a drain of the second transistor is coupled a drain of a third transistor; and sourcing a current to the third transistor, wherein during a light load condition of the power supply circuit, the current varies based on the voltage at a Vout node of the power supply circuit, and during a heavy load condition of the power supply circuit, the current is limited based on a current threshold.

Abstract: Amplifier circuits provide operation with low-distortion zero crossings outside of a unipolar power supply voltage range. The amplifiers include multiple driver circuits and a control circuit. The control circuit selects between actively operating selected ones of the multiple driver circuits or all of the multiple driver circuits, according to an input signal to be reproduced by one or more of the multiple amplifier driver circuits. The control circuit determines a splice point at which the control circuit selects between actively operating selected ones of the multiple driver circuits or all of the multiple driver circuits.

Abstract: A power amplifier circuit includes a first amplifier circuit configured to amplify a first signal of a first frequency band and output a first amplified signal having a first power, a second amplifier circuit configured to amplify a second signal of the first frequency band or a second frequency band different from the first frequency band and output a second amplified signal having a second power different from the first power, and a first variable adjustment circuit disposed between the second amplifier circuit and a first circuit subsequent to the second amplifier circuit, the first variable adjustment circuit being configured to be capable of adjusting a first impedance of the first circuit seen from the second amplifier circuit.

Abstract: A method for matching a pair of composite circuit elements (CEs) included in a circuit includes fabricating N CEs (e.g., resistors, transistors, current sources, capacitors) designed to match and switches configurable, according to M different combinations, to connect N/2 of the N CEs to form a first composite CE and to connect a remaining N/2 of the N CEs to form a second composite CE. Sequentially in time, for each combination of the M combinations, the switches are configured to form the first and second composite CEs according to the combination and a characteristic of the circuit is measured that includes the formed first and second composite CEs. The characteristic indicates how well the formed composite CEs match. A final combination of the M combinations is chosen whose measured characteristic indicates a best match and the final combination is used to configure the switches to form the composite CEs.

Abstract: Apparatus and methods for amplifier input-overvoltage protection with low leakage current are provided herein. In certain embodiments, amplifier input circuitry for an amplifier includes a pair of input terminals, a pair of input transistors each having a control input (for instance, a transistor gate), a pair of protection transistors each connected between one of the input terminals and the control input of a corresponding one of the input transistors, and a bidirectional clamp connected between the control inputs of the input transistors. Implementing the amplifier input circuitry in this manner provides a number of advantages including, but not limited to, robust protection against input overvoltage and low input-leakage current.

Abstract: In a differential amplifier circuit, a differential amplifier circuit unit includes: first and second transistors provided between a current source circuit and a load circuit, which receives differential input signals at gates to generate differential output signals at drains; and a third transistor connected between sources of the first and second transistors, which receives a control signal at a gate. A replica amplifier circuit unit includes: a voltage generation circuit which generates first and second reference voltages; first and second replica transistors which receives the first and second reference voltages at gates to generate replica output signals at drains; a third replica transistor connected between sources of the first and second replica transistors, which receives the control signal at a gate; and an operational amplifier which generates the control signal according to a difference between at least one of the first and second reference voltages and the replica output signal.

Abstract: A dc coupled amplifier includes a pre-driver, and amplifier and a bias control circuit. The pre-driver is configured to receive one or more input signals and amplify the one or more input signals to create one or more pre-amplified signals. The amplifier has cascode configured transistors configured to receive and amplify the one or more pre-amplified signals to create one or more amplified signals, the amplifier further having an output driver termination element. The bias control circuit is connected between the pre-driver and the amplifier, the bias control circuit receiving at least one bias current from the output driver termination element of the amplifier, wherein the pre-driver, the amplifier and the bias control circuit are all formed on a same die.

Abstract: An amplifier with enhanced slew rate includes an input stage including a first channel coupled to receive differential inputs and a second channel coupled to receive the differential inputs; a middle stage including a first current source coupled to receive outputs of the second channel and electrically connected to power, a second current source coupled to receive outputs of the first channel and electrically connected to ground, and a floating current source electrically connected between the first current source and the second current source; and an output stage coupled to the middle stage to generate an output voltage. A transit circuit is disposed in the input stage or the middle stage, controlled by the output stage, and configured to supply extra current during signal transition of the differential inputs, thereby enhancing the slew rate.

Abstract: A voltage driver circuit for an output stage of an operational amplifier, or other circuits, includes a level shifter and an output driver including a source follower and a common source amplifier in a push-pull configuration. The level shifter generates a node voltage as a function of an input voltage on the input node. The output driver including a first transistor having a control terminal receiving the node voltage, and connected between a supply voltage and an output node, and a second transistor having a control terminal receiving the input voltage from the input node, and connected between the output node and a reference voltage, wherein the first and second transistors have a common conductivity type.

Abstract: A driver circuit includes a differential pair of transistors that amplify differential input signals and output the amplified differential input signals from signal output terminals, a current source that supplies a constant current to the differential pair of transistors, a switch that stops the current supply from the current source to the differential pair of transistors during a shutdown mode period, capacitors each having one end connected to the ground, a switch that connects the capacitor to the signal output terminal during the shutdown mode period and disconnects the capacitor from the signal output terminal during an amplification mode period, and a switch that connects the capacitor to the signal output terminal during the shutdown mode period and disconnects the capacitor from the signal output terminal during the amplification mode period.

Abstract: A variable-gain amplifier and a phased array system are provided. A variable-gain amplifier includes a cascode circuit comprising a first amplification transistor and a second amplification transistor array that are cascaded, the second amplification transistor array comprising a plurality of second amplification transistors connected in parallel and configured to output an adjustable current to an output matching network, the first amplification transistor is a common-source transistor, the plurality of second amplification transistors are common-gate transistors, or the cascode circuit is a common-emitter common-base circuit, the first amplification transistor is a common-emitter amplification circuit, and the second amplification transistor array is a common-base amplification circuit. The variable-gain amplifier further including a variable capacitor circuit coupled to the second amplification transistor array and coupled to the output matching network at first nodes.

Abstract: A tank circuit (200) includes a tunable resonator subcircuit (210) having a first control input and having an effective parallel resistance that varies with tuning of the tunable resonator subcircuit (210). The tank circuit (200) further comprises a variable negative-resistance subcircuit (250) having a second control input and coupled in parallel to the tunable resonator subcircuit (210), where the variable negative-resistance subcircuit (250) is configured to provide a variable negative resistance, responsive to the control input, so as to increase the effective parallel resistance of the tank circuit (200).

Abstract: A circuit includes a transistor input pair, a differential input having a comparator input, and a level shifter. The transistor input pair is adapted to be coupled between a voltage supply and a comparator output. The transistor input pair includes a first transistor having a gate and a drain. The drain of the first transistor is coupled to the comparator output. The level shifter is coupled between the transistor input pair and the differential input. The level shifter includes a second transistor having a gate and a source. The gate of the second transistor is coupled to the comparator input. The source of the second transistor is coupled to the gate of the first transistor.

Abstract: A complementary envelope detector contemplates using two pair of mirrored transistors to provide a differential output envelope signal to an associated envelope tracking integrated circuit (ETIC) that supplies control voltages to an array of power amplifiers. While bipolar junction transistors (BJTs) may be used, other exemplary aspects use field effect transistors (FETs). In an exemplary aspect, a first pair are negative channel FETs (nFETs) and a second pair are positive channel FETs (pFETs).

Abstract: A receiver front end capable of receiving and processing intraband non-contiguous carrier aggregate (CA) signals using multiple low noise amplifiers (LNAs). Cascode circuits, each having a “common source” configured input FET and a “common gate” configured output FET, serve as the LNAs. An amplifier-branch control switch, configured to withstand relatively high voltage differentials by means of a relatively thick gate oxide layer and coupled between a terminal of the output FET and a power supply, controls the ON and OFF state of each LNA while enabling use of a relatively thin gate oxide layer for the output FETs, thus improving LNA performance. Some embodiments may include a split cascode amplifier and/or a power amplifier.

Abstract: An analog to digital convertor circuit includes an input circuit and a switched capacitor circuit. The input circuit is configured to selectively drain a first current from a first node or drain a second current from a second node according to a first bit and a second bit that have opposite logic values. The switched capacitor circuit is configured to compensate a capacitance value of one of the first node and the second node according to the first bit and the second bit.

Abstract: An amplifier includes a first stage and a second stage. The first stage includes a first output and a second output. The second stage includes an output, a first transistor and a second transistor. The first transistor includes a drain coupled to the first output of the first stage, and a source coupled to the output of the second stage. The second transistor includes a drain coupled to the second output of the first stage, and a gate coupled to the output of the second stage.

Abstract: A buffer circuit includes a first transistor, a second transistor, and a third transistor. The first transistor includes a first current terminal, a second current terminal, and a control terminal. The first current terminal is coupled to a load terminal. The control terminal is coupled to a preamplifier input terminal. The second transistor includes a first current terminal and a second current terminal. The first current terminal of the second transistor is coupled to the second current terminal of the first transistor. The third transistor includes a first current terminal, a second current terminal, and a control terminal. The first current terminal of the third transistor is coupled to the load terminal. The second current terminal of the third transistor is coupled to a ground terminal. The control terminal of the third transistor is coupled to second current terminal of the second transistor.

Abstract: The present invention is gallium nitride based operational amplifier because reliability and performance of the gallium nitride is better than the silicon counterpart in radiation environment. The operational amplifier includes four stages, first stage is dual input balanced output differential amplifier, second stage is dual input unbalanced differential amplifier, third stage is buffer stage to couple second and fourth stage, and fourth stage is cascaded common source amplifier with degeneration. A capacitor coupled between second and third stage is to enhance the stability of operational amplifier.

Abstract: A noise filtering circuit, a digital to analog converter and an electronic device are provided. The noise filtering circuit comprises a first amplifier configured to receive a bias voltage at a first input terminal, receive a bias output voltage at a second input terminal though a feedback path, and compensate for a difference between the bias voltage and the bias output voltage; a first transistor connected to an output of the first amplifier and having a gate to which an off-voltage is applied; a first capacitor connected to the first transistor; a second capacitor connected to the output of the first amplifier; a second transistor connected to the second capacitor and having a gate to which an off-voltage is applied, and a second amplifier having an input terminal connected to the first capacitor and a second input terminal connected to the second transistor.

Abstract: A new trans-impedance amplifier (TIA) with low noise is provided. The TIA may include an input stage and an output driving stage. The input stage may include a pair of input PMOS transistors, a pair of input NMOS transistors, and a pair of differential voltage input nodes. The output driving stage may include a pair of output circuits, each may include a first pair of PMOS and NMOS transistors electrically connected in parallel, a second pair of PMOS and NMOS transistors electrically connected in series, and a pair of capacitors electrically connected in series, which are electrically connected in parallel. The structure can lead to a reduced noise level of the TIA.

Abstract: A differential amplifying unit includes a first input transistor and a second input transistor forming a differential pair, and a first tail current source and a second tail current source. An output stage includes a first output transistor and a second output transistor that can be driven by an output of the differential amplifying unit. A controller performs control such that during startup, a load is driven by the first tail current source and the first output transistor, and such that after startup, the load is driven by the first tail current source, the second tail current source, the first output transistor, and the second output transistor.

Abstract: A semiconductor device includes a low power fast differential transconductor, which provides an output current as a function of a difference between a reference potential input and a feedback potential input. The transconductance increases as an absolute value of the difference between the reference potential and the feedback potential increases. The transconductor includes a reference input stage to receive the reference potential and a reference load coupled in series with the reference input stage. The transconductor includes a feedback input stage to receive the feedback potential and a feedback load coupled in series with the feedback input stage. The transconductor further includes a current limiting component that is configured to control a total current through the reference input stage and the feedback input stage.

Abstract: The present disclosure provides a comparator and a decision feedback equalization circuit. The comparator includes: a first sampling circuit provided with an output terminal, and configured to generate, under the control of a first control signal and a clock signal, a first differential signal according to a signal to be compared and a first reference signal; a second sampling circuit provided with an output terminal connected to the output terminal of the first sampling circuit, and configured to generate, under the control of a second control signal and the clock signal, a second differential signal according to the signal to be compared and a second reference signal, where the first reference signal is larger than the second reference signal.

Abstract: Methods, systems, and devices for crosstalk cancellation for signal lines are described. In some examples, a device (e.g., a host device or a memory device) may generate a first signal and may invert the first signal to obtain an inverted first signal. The device may obtain a second signal based on attenuating a first range of frequencies of the inverted first signal and a second range of frequencies of the inverted first signal, where the first range of frequencies is below a first threshold frequency and the second range of frequencies is above a second threshold frequency that is greater than the first threshold frequency. The device may transmit the first signal via a first signal line of a set of signal lines and the second signal line via a second signal line of the set of signal lines.

Abstract: A compensated amplifier for use in a power converter controller. The compensated amplifier comprises a first amplifier, a second amplifier, an integrator, and an arithmetic operator. The first amplifier coupled to receive a sensed signal and a reference signal and configured to generate a first error signal in response to the sensed signal and the reference signal. The second amplifier coupled to the first amplifier and configured to generate a second error signal in response to the sensed signal and the reference signal. The integrator coupled to the first amplifier and configured to generate an integrated error signal in response to the first error signal. The arithmetic operator coupled to the integrator and to the second amplifier, wherein the arithmetic operator is configured to generate a control signal in response to the integrated error signal and the second error signal.

Abstract: A communication device includes a power amplifier that generates power signals according to one or more operating bands of communication data, with the amplitude being driven and generated in output stages of the power amplifier. The final stage can include an output passive network that suppresses suppress an amplitude modulation-to-phase modulation (AM-PM) distortion. During a back-off power mode a bias of a capacitive unit of the output power network component can be adjusted to minimize an overall capacitance variation. An output passive network can further generate a flat-phase response between dual resonances of operation.

Abstract: Enhanced operational amplifier trim circuitry and techniques are presented herein. In one implementation, a circuit includes a reference circuit configured to produce a set of reference voltages, and a digital-to-analog conversion (DAC) circuit. The DAC circuit comprises a plurality of transistor pairs, where each pair among the plurality of transistor pairs is configured to provide portions of adjustment currents for an operational amplifier based at least on the set of reference voltages and sizing among transistors of each pair. The circuit also includes drain switching elements coupled to drain terminals of the transistors of each pair and configured to selectively couple one or more of the portions of the adjustment currents to the operational amplifier in accordance with digital trim codes.

Abstract: A distributed power management circuit is provided. In embodiments disclosed herein, the distributed power management circuit can achieve multiple performance enhancing objectives simultaneously. More specifically, the distributed power management circuit can be configured to switch a modulated voltage from one voltage level to another within a very short switching window, reduce in-rush current required for switching the modulated voltage, and minimize a ripple in the modulated voltage, all at same time. As a result, the distributed power management circuit can be provided in a wireless device (e.g., smartphone) to enable very fast voltage switching across a wide modulation bandwidth (e.g., 400 MHz) with reduced power consumption and voltage distortion.

Abstract: A power amplifier includes: a power amplification circuit and a linearity compensation circuit; and herein the linearity compensation circuit is connected between a transistor amplification circuit and a biasing circuit of the power amplification circuit, to linearly compensate a nonlinear distortion of the power amplification circuit.

Abstract: A circuit includes an operational amplifier having: a positive input; a negative input; an operational amplifier output; a differential front end; a positive channel (PCH) input stage; a negative channel (NCH) input stage; and an output stage. The operational amplifier also includes a current limit circuit coupled to an output of the output stage and including: an output current sense voltage circuit having an output configured to provide an output current sense voltage; an indirect current feedback circuit coupled to the output of the output current sense voltage circuit, the indirect current feedback circuit having an output configured to provide an output current feedback sense voltage responsive to the output current sense voltage; and control circuitry coupled to the indirect current feedback circuit and configured vary a resistance between the output stage output and ground responsive to a difference between the output current feedback sense voltage and a reference voltage.

Abstract: Differential input circuits employ protection transistors and feedback paths to limit the differential voltage applied to input transistors. In an example arrangement, a differential input voltage is applied to terminals of the protection transistors, and current paths couple the respective protection transistors to control terminals of the input transistors, respectively. A control terminal drive voltage source is coupled to the control terminals of the input protection transistors to control the drive voltage applied to those terminals. Feedback paths, one for each of the input transistors, control voltages applied to the control terminals of the input transistors, maintaining the input differential voltage at a relatively low level and defined by the product of a specified current value and a specified resistance value.

Abstract: An active electrode has an electrode for sensing an electric potential and generating an input signal, and a shield placed near the electrode but being electric insulated from the electrode. An integrated amplifier (10) has an input connected to the at least one electrode for receiving the input signal, and providing a buffered path outputting a buffered output signal. The shield being connected to the output of the integrated amplifier to actively drive the electrical potential of the shield, thereby providing an active shielding of the electrode. The buffered path includes a first mixer (11) in front of the integrated amplifier for frequency shifting the input signal from a basic frequency range to a higher frequency range, and a second mixer (12) on the output of the integrated amplifier for frequency shifting the amplified signal from the higher frequency range back to the basic frequency range. The active electrode may be used for recording EEG signals.

Abstract: Provided is an output amplifier having: a push-pull output-stage formed by first and second output-stage transistors; and a detection circuit detecting an abnormal output current output by the output amplifier and including: a coupling circuit, generating first and second currents mirroring current flowing in the first output-stage transistor and third and fourth currents mirroring current flowing in the second output-stage transistor, coupling the first and third currents at a first output node, outputting a first voltage at the first output node, coupling the second and fourth currents at a second output node, and outputting a second voltage at the second output node; and a determination circuit, outputting a determination signal indicating normality of an output current based on the first and second voltages. The coupling circuit generates the first to fourth currents. In the reference state, the third current >the first current, the second current >the fourth current.

Abstract: An amplifier circuit includes a voltage-to-current conversion circuit and a current-to-voltage conversion circuit. The voltage-to-current conversion circuit generates a current signal according to an input voltage signal, and includes an operational transconductance amplifier (OTA) used to output the current signal at an output port of the OTA. The current-to-voltage conversion circuit generates an output voltage signal according to the current signal, and includes a linear amplifier (LA), wherein an input port of the LA is coupled to the output port of the OTA, and the output voltage signal is derived from an output signal at an output port of the LA.

Abstract: A compact ADC circuit can include one or more comparators, and a serial DAC (Digital-to-Analog) circuit that provides a signal to the comparator (or comparators). In addition, the ADC circuit can include a serial DAC redistribution sequencer that can provide a plurality of signals as input to the serial DAC circuit and is subject to a redistribution cycle and which receives as input a signal from a data multiplexer whose input connects electronically to an output of the comparator. The circuit can further include an ADC code register that provides an ADC output that connects electronically to the output of the comparator and the input to the data multiplexer. Shared logic circuitry for sharing common logic between pixels can be included, wherein the shared logic circuitry connects electronically to the data multiplexer and the ADC code register, wherein the shared logic circuitry promotes area and power savings for the pixel detector circuit.

Abstract: Aspects of the present disclosure provide a method for regulating an integration current of a sensing amplifier. The sensing amplifier includes a first input transistor and a second input transistor, wherein a source of the first input transistor and a source of the second input transistor are coupled to a source node. The method includes pulling a current from or sourcing the current to the source node, measuring the integration current, comparing the measured integration current with a reference signal, and adjusting the current pulled from or sourced to the source node based on the comparison.

Abstract: A method of temperature compensation in an optical-fingerprint detection system includes acquiring a first reading associated with one or more pixels of an array. The first reading is a baseline reading. The method further includes acquiring a second reading associated with the one or more pixels of the array. The second reading includes the baseline plus a signal. Producing a temperature compensated signal reading by subtracting the first reading from the second reading. The array is an optical-fingerprint array, and each pixel of the array is coupled to a readout circuit via a pixel switch. The method includes row-based and frame-based schemes and a blind pixel scheme. Readout circuit improvements including multiplexed analog front-end (AFE), charge magnifier with column charge offset compensation and a low-noise gate driver circuit are provided.

Abstract: An electronic amplification-interface circuit includes a differential-current reading circuit having a first input terminal and a second input terminal. The differential-current reading circuit includes a continuous-time sigma-delta conversion circuit formed by an integrator-and-adder module generating an output signal that is coupled to an input of a multilevel-quantizer circuit configured to output a multilevel quantized signal. The integrator-and-adder module includes a differential current-integrator circuit configured to output a voltage proportional to an integral of a difference between currents received at the first and second input terminals. A digital-to-analog converter, driven by a respective reference current, receives and converts the multilevel quantized signal into a differential analog feedback signal. The integrator-and-adder module adds the differential analog feedback signal to the differential signal formed at the first and second input terminals.