Abstract: A transconductance adjusting circuit includes: a voltage generating section configured to generate a first differential voltage; a first transconductance amplifier configured to receive the first differential voltage through a first positive-phase voltage transmission line and a first reversed-phase voltage transmission line, and output a second differential voltage through a second positive-phase voltage transmission line and a second reversed-phase voltage transmission line; a first control section configured to receive the second differential voltage and supply a first control voltage to the first transconductance amplifier; a second control section configured to receive the second differential voltage and supply a second control voltage to the first transconductance amplifier; a first resistor section that makes a connection between the first positive-phase voltage transmission line and the second positive-phase voltage transmission line; and a second resistor section that makes a connection between the f

Abstract: An envelope detector (ED) includes a voltage-mode ED core including parallel detection transistors for detecting a voltage envelope of a radio frequency (RF) signal input, the RF signal input including an output of a radio such as a cellular transmitter (TX). The ED further includes multiple voltage amplifiers positioned serially in gain stages between the TX output and the ED core to provide a total linear voltage range of the envelope detector. A final voltage amplifier of the multiple voltage amplifiers drives the ED core and includes a class-AB RF amplifier configured to operate within a full linear voltage range of the ED core.

Abstract: Circuits, devices and methods are provided, such as an amplifier (e.g., a voltage regulator) that includes a feedback circuit that supplies negative feedback through a feedback path. One such feedback path includes a capacitance coupled in series with a “one-way” isolation circuit through which a feedback signal is coupled. The “one-way” isolation circuit my allow the feedback signal to be coupled from a “downstream” node, such as an output node, to an “upstream” node, such as a node at which an error signal is generated to provide negative feedback. However, the “one-way” isolation circuit may substantially prevent variations in the voltage at the upstream node from being coupled to the capacitance in the isolation circuit. As a result, the voltage at the upstream node may quickly change since charging and discharging of the capacitance responsive to voltage variations at the upstream node may be avoided.

Abstract: A new inverter-based fully-differential amplifier is provided including one or more common-mode feedback transistors coupled to each inverter, which transistors operate in the liner region. Accordingly, due to the fully-differential nature of the new inverter-based fully-differential amplifier, the amplifier provides an improved Power Supply Rejection Ratio (PSRR), provides a reduced sensitivity to supply voltage and process or part variations, and does not require an auto-zeroing technique to be utilized, which ultimately saves power, all while utilizing the low-voltage and low-power advantages of an inverter-based design.

Abstract: A driver for an analog-to-digital converter (ADC) has an overall feedback loop between its input and its output for maintaining overall accuracy, and a much faster feedback loop in its output stage that quickly compensates for output transients before the overall feedback loop can substantially react to the transients. Output voltage transients are created by the intermittent capacitive load of the ADC. The fast feedback loop can be made very fast since there are only a few components in the fast feedback path. The fast reduction of the output transients enables a shorter sampling time, leading to more accurate analog-to-digital conversion. The overall gain of the driver can be set to be greater than unity while still providing good output transient suppression.

Abstract: Apparatuses and methods are disclosed, including an apparatus with a first differential amplifier to amplify an input signal into a first output signal, a second differential amplifier to amplify the input signal into a second output signal that is complementary to the first output signal, and a feedback resistance coupled between the first output signal and the second output signal. Additional apparatuses and methods are described.

Abstract: An integrated circuit can comprise: a first port, a second port, and a third port; and a plurality of microwave operational amplifiers coupled to each other and the first port, the second port, and the third port. The plurality of microwave operational amplifiers can be arranged to substantially pass a signal provided to the first port to the second port while substantially isolating the signal provided to the first port from the third port; the plurality of microwave operational amplifiers can be arranged to substantially pass a signal provided to the second port to the third port while substantially isolating the signal provided to the second port from the first port; and the plurality of microwave operational amplifiers can be arranged to substantially pass a signal provided to the third port to the first port while substantially isolating the signal provided to the third port from the second port.

Abstract: According to one embodiment, a high performance buffer for use in a communications system includes first and second differential blocks. Each of the first and second differential blocks comprise one or more driving transistors for generating a driving current for a load of the high performance buffer, and a feedback path for adjusting the operation of the one or more driving transistors. The feedback path includes a feedback transistor for receiving a common mode bias voltage, wherein the common mode bias voltage depends at least in part on a threshold voltage of the feedback transistor. The feedback path includes a programmable resistor and capacitor to reduce out of band loop gain and the noise. The high performance buffer is configured to achieve a high linearity, low output impedance, and low noise, and is suitable for use as a pre-mixer buffer in a wireless communications system.

Abstract: An amplifier, comprising: an input node; an output node; a gain stage having a gain stage inverting input, a gain stage non-inverting input and a gain stage output; a feedback capacitor connected in a signal path between the gain stage output and the gain stage inverting input; a sampling capacitor connected between the input node and the gain stage non-inverting input, and a controllable impedance in parallel with the feedback capacitor, wherein the controllable impedance is operable to switch between a first impedance state in which it does not affect current flow through the feedback capacitor, and a second impedance state in which it cooperates with the feedback capacitor form a bandwidth limiting circuit.

Abstract: Apparatuses for generating negative impedance compensation are provided. Embodiments include a differential amplifier having a first output and a second output; a capacitor coupled between the first output and the second output of the differential amplifier; a first negative impedance cross-coupled circuit having a first output and a second output; and a resistance control circuit coupled in series between the first output and the second output of the differential amplifier and the first output and the second output of the first negative impedance cross-coupled circuit.

Abstract: Amplifier architectures are provided for current sensing applications. An amplifier includes a load device, an operational amplifier, a current source, and a bipolar transistor. The operational amplifier has a first input terminal connected to a first input node that receives an input current, and a second input terminal connected to a second input node that receives a reference voltage. The current source is connected to an output of the operational amplifier. The operational amplifier, the current source, and the bipolar transistor form a feedback loop that generates and maintains a bias voltage on the first input node based on the reference voltage applied to the second input node. The bipolar transistor amplifies the input current received on the first input node, and generates an amplified input current. The load device converts the amplified input current to an output voltage, wherein the output voltage is used to sense the input current.

Abstract: A transformer is provided. The transformer includes at least one first primary turn; at least one second primary turn; and a first secondary turn and a second secondary turn. The first secondary turn and the second secondary turn are arranged laterally between the at least one first primary turn and the at least one second primary turn. The first secondary turn and the second secondary turn are arranged one above the other.

Abstract: An operational amplifier has two paths, a high frequency path and a low frequency path. In addition, it has three main sections of stages. A stage converts input voltage to an amplified output voltage, a stage converting an input voltage in to an output current and a final stage where the outputs of the two previous sections are supplied as inputs. Among them, the final stage acts as a voltage follower to a signal applied to its plus (+) input and as a transimpedance amplifier for a signal applied to its minus input (?). In this configuration, a path for low frequencies and a path for high frequencies are created in a single operational amplifier.

Abstract: Apparatus and methods are disclosed related to trimming an input offset current of an amplifier. One such apparatus can include auxiliary bipolar transistors connected in parallel with bases of respective bipolar transistors of an input stage of an amplifier. The auxiliary bipolar transistors can be biased such that the base currents of the auxiliary bipolar transistors compensate for a mismatch in base currents of the bipolar transistors of the input stage of an amplifier. The offset current at an input of an amplifier can be reduced independent of an offset voltage at the input of the amplifier.

Abstract: A three stage amplifier is provided and the three stage amplifier comprises a first gain stage, a second gain stage and a third gain stage wherein said first stage receives an amplifier input signal and said third gain stage outputs an amplifier output signal. The amplifier includes a feedback loop having a current buffer and a compensation capacitance provided from the output of said third gain stage to the output of the first gain stage. In addition, an active left half plane zero stage is embedded in said feedback loop for cancelling a parasitic pole of said feedback loop.

Abstract: Described herein is a low power high-speed digital receiver. The apparatus of the receiver comprises: a sampling unit operable to sample a differential input signal and to boost input signal gain, the sampling unit to generate a sampled differential signal with boosted input signal gain; and a differential amplifier to amplify the sampled differential signal with boosted input signal gain, the differential amplifier to generate a differential amplified signal.

Abstract: A circuit includes a bias generating circuit, an operational amplifier, and a current mode logic circuit. The operational amplifier has a first input terminal, a second input terminal, and an output terminal. The bias generating circuit is configured to provide a first bias voltage to the first terminal. The second terminal is configured to receive a second bias voltage. The second terminal and the output terminal are configured to form a negative feedback loop. The output terminal is coupled with the current mode logic circuit.

Abstract: An amplifier applies a self-adapting voltage to an output terminal. A bias circuit provides a greater bias current in a first external connection condition, in the absence of a pull-up resistance connected to the output terminal, than when such a pull-up resistance is present. The amplifier applies a different voltage to the output terminal in the absence of a pull-up resistance than when such a pull-up resistance is present. The circuit can be used in a portable device for receiving charging current from a battery charger through a connector having a D+ pin for connection to the battery charger and connected to the amplifier output terminal for battery charger detection. The portable device can meet the USB battery charger specification rev. 1.2.

Abstract: A method includes, in at least one aspect, receiving, at both an input node of a first input stage and in input node of a second input stage, a single-ended voltage signal; providing, by at least one of the first input stage or the second input stage, inductive degeneration to the single-ended voltage signal; converting an output from the first input stage into a first single-ended current signal; converting an output from the second input stage into a second single-ended current signal; and outputting, by an output stage, a differential output including the first single-ended current signal and the second single-ended current signal.

Abstract: An apparatus includes a pass element comprising an input, an output and a control input. The pass element, with a first signal on the control input, passes a voltage from the input to the output and, with a second signal on the control input, blocks the voltage on the input from passing to the output. A differential amplifier includes a non-inverting input coupled to the input, an inverting input coupled to the output, an amplifier output coupled to the control input and a bias current connection. The differential amplifier, with a bias current supplied, supplies the first signal along with a closed feedback loop from the output and supplies the second signal in absence of the bias current. A current source is coupled to the bias current connection and an enable input. The current source supplies the bias current and, in absence of an enable signal, disables the bias current.

Abstract: A preamplifier includes a differential pair of transistors receiving a bias current having a differential input and a differential output, a first resistor coupled to a first differential output node, a first transistor having a current path coupled between the first resistor and a power supply, a second resistor coupled to the first differential output node, a second transistor having a current path coupled between the second resistor and the power supply, a third resistor coupled to a second differential output node, a third transistor having a current path coupled between the third resistor and the power supply, a fourth resistor coupled to the second differential output node, and a fourth transistor having a current path coupled between the fourth resistor and the power supply, wherein a source of the second and third transistors are coupled together.

Abstract: When a switch is set to off, and a switch is set to on, the voltage of a SigOut terminal is stabilized with a reference voltage, and a bias voltage is applied to a capacitor. Changing the switch from on to off, with the bias voltage retained in the capacitor, a detection signal which is input via a SigIn terminal is amplified with the reference voltage as a reference, and an amplified signal is output from the SigOut terminal.

Abstract: An amplifier circuit includes a digital amplifier configured to amplify an input signal to output a first output signal, an analog amplifier configured to amplify the input signal to output a second output signal, a check circuit configured to produce a check signal responsive to frequencies of the input signal, and a selector circuit configured to select and output one of the first output signal and the second output signal in response to the check signal.

Abstract: A method of operating an amplifier circuit having a pre-charge phase and a sample/conversion phase includes, during a pre-charge phase, charging first and second capacitors to first and second bias voltages. The first capacitor is coupled to a first input of an amplifier circuit, which has a second input and an output. The second capacitor is coupled to the second input. During a sample/conversion phase, the first input of the amplifier circuit is coupled to an input signal through the first capacitor to level-shift the input signal according to the first bias voltage and the output of the amplifier is coupled to the second input through the second capacitor to level shift a feedback signal according to the second bias voltage.

Abstract: An amplifier circuit capable of reducing load of a circuit at the previous stage by providing increased input impedance producing less noises. The amplifier circuit includes a fully-differential operational amplifier composed of an inverting input terminal, a non-inverting input terminal receiving a signal different from a signal to be input to the inverting input terminal, an inverting output terminal with the same polarity of the inverting input terminal, and a non-inverting output terminal with reverse polarity; an input impedance element with one end connected to the inverting input terminal; an input impedance element with one end connected to the non-inverting input terminal; and positive feedback impedance elements, with one end of connected to the other end of the input impedance element and the other end connected to the inverting output terminal or to the non-inverting output terminal.

Abstract: An amplifier circuit includes differential input nodes, a differential amplifier stage having differential input terminals and differential output terminals, and an input common-mode voltage adaptation circuit connected between the differential input nodes of the amplifier circuit and the differential input terminals of the differential amplifier stage. During an input common-mode adaptation phase, the input common-mode voltage adaptation circuit forces the differential input terminals of the differential amplifier stage to a common-mode voltage equal to an adaptive reference voltage, independent of a common-mode voltage applied to the differential input nodes of the amplifier circuit during the input common-mode adaptation phase.

Abstract: A high-frequency bandwidth amplifying circuit includes a forward channel and a backward channel. An input terminal of the forward channel and an external forward input terminal are connected; an output terminal of the forward channel and a forward output port are connected. An input terminal of the backward channel and an external backward input terminal are connected; an output terminal of the backward channel and a backward output port are connected. The high-frequency bandwidth amplifying circuit further includes a feedback network. The forward channel includes a first operational amplifier and a second operational amplifier. An input terminal of the first operational amplifier is connected to the external forward input terminal; an output terminal of the first operational amplifier is connected to an input terminal of the second operational amplifier; and an output terminal of the second operational amplifier is connected to the forward output port.

Abstract: Disclosed are various embodiments of a current-mode line driver that may facilitate transmitting signals to a load. The current-mode line driver may comprise a common-mode current sense element that provides a signal corresponding to the common-mode output current of the line driver. A transconductance element receives the signal from the common-mode current sense element and provides a compensating current that is based at least in part on the signal. The compensating current may reduce the common-mode output current of the line driver.

Abstract: The present disclosure provides an earphone power amplifier, including a ground contact connected to a ground wire of an earphone, a left sound channel power amplifying circuit connected to a left sound channel of the earphone, and a right sound channel power amplifying circuit connected to a right sound channel of the earphone. The left sound channel power amplifying circuit includes a first operational amplifier and a first positive feedback exported from an input end of the first ferrite bead to an in-phase input end of the first operational amplifier, the right sound channel power amplifying circuit includes a second operational amplifier and a second positive feedback exported from the input end of the first ferrite bead to an in-phase input end of the second operational amplifier.

Abstract: A system for a feedback transimpedance amplifier with sub-40 khz low-frequency cutoff is disclosed and may include amplifying electrical signals received via coupling capacitors utilizing a transimpedance amplifier (TIA) having feedback paths comprising source followers and feedback resistors. Gate terminals of the source followers may be coupled to output terminals of the TIA. The feedback paths may be coupled prior to the coupling capacitors at inputs of the TIA. Voltages may be level shifted prior to the coupling capacitors to ensure stable bias conditions for the TIA. The TIA may be integrated in a CMOS photonics chip and the source followers may comprise CMOS transistors. The TIA may receive current-mode logic or voltage signals. The electrical signals may be received from a photodetector, which may comprise a silicon germanium photodiode differentially coupled to the TIA. Optical signals for the photodetector in the CMOS photonics chip may be received via optical fibers.

Abstract: A CMOS trans-impedance amplifier (TIA) in accordance with the present disclosure can achieve improved bandwidth and sensitivity by utilizing novel shunt-shunt feedback and inductor peaking. The proposed design simultaneously improves 10-Gbps TIA performance in terms of bandwidth and sensitivity, while the TIA may be fabricated through a standard 0.13 ?m CMOS process. Performance of the TIA in accordance with the present disclosure is much better than that of conventional CMOS TIA in the 10-Gbps CMOS TIA design and applications.

Abstract: A method of designing a microwave filter using a computerized filter optimizer, comprises generating a filter circuit design in process (DIP) comprising a plurality of circuit elements having a plurality of resonant elements and one or more non-resonant elements, optimizing the DIP by inputting the DIP into the computerized filter optimizer, determining that one of the plurality of circuit elements in the DIP is insignificant, removing the one insignificant circuit element from the DIP, deriving a final filter circuit design from the DIP, and manufacturing the microwave filter based on the final filter circuit design.

Abstract: A method of fabricating an instrumentation amplifier to have an improved common mode rejection ratio (CMRR) vs. frequency initially trims resistors in the input amplifiers of the instrumentation amplifier during a DC test, where the inputs are shorted and a DC voltage is applied, so that the output of the amplifier is approximately zero. This will normally cause the transconductances of the two input amplifiers to be different. Thus, the AC CMRR will degrade with frequency. Trimmable capacitors are provided in the input section and are trimmed during a common mode AC test to cause the output voltage to be minimized during the AC test. This causes the two input amplifiers to have the same bandwidth and gm/C ratio.

Abstract: A common mode control circuit (400) for generating a control signal indicative of a common mode signal in first and second signals of a differential signal pair comprises a first charge control means (300) for varying, dependent on polarity of the first and second signals with respect to a threshold, charge on a capacitive element (250, 260, 270). The first charge control means (300) is operable to, in response to the first and second signals both switching polarity simultaneously from opposite polarities, maintain a direction of flow of the charge. The first charge control means (300) can be operable to, in response to the first and second signals both switching polarity simultaneously from opposite polarities and the flow of charge being zero, maintain the flow at zero.

Abstract: Representative implementations of devices and techniques provide a linearized high-ohmic resistor. In an example, a quantity of serially connected nonlinear impedances is arranged as a resistance. In one example, the quantity of impedances is applied in an amplifier circuit, between an input of the amplifier and an output of the amplifier, and arranged to set a DC operating point for the amplifier.

Abstract: A low noise amplifier is used to amplify a differential input pair to generate a differential output pair. The low noise amplifier includes two main paths, two assistant circuits and two adders to make noise carried on two output signals of the differential output pair be the same; therefore, the noise of the two output signals can be fully cancelled in the following operations.

Abstract: Amplifiers with voltage and current feedback error correction are provided. In one embodiment, an amplifier includes a first input terminal, a second input terminal, an output terminal, a first stage, and a voltage feedback amplification circuit. The first stage can be used to generate first and second output currents, which can be used to control a voltage level of the output terminal. The first and second output currents can change in response to a current feedback signal and a differential input signal received between the first and second input terminals. The first stage can also generate a voltage feedback signal, which can be used by the voltage feedback amplification circuit to control a voltage level of the second input terminal based on a voltage level of the first input terminal.

Abstract: A system and method for adjusting a common mode output voltage in an instrumentation amplifier is provided. In one aspect, the common mode output voltage is increased or decreased with respect to the common mode input voltage to enable high amplification of the signal input to the instrumentation amplifier. Moreover, the common mode output voltage can be driven to (or approximately to) a target voltage value such as, but not limited to, half the supply, even if the common mode input voltage is close to supply or ground rail voltage. Thus, a high amplification of the differential input voltage can be obtained and utilized for various applications requiring rail to rail input.

Abstract: An amplifier with improved noise reduction is disclosed. In one implementation, an amplifier is provided that includes a main output stage configured to output an amplified signal at a main output terminal, a secondary output stage configured to output a copy of the amplified signal at a secondary output terminal, and a signal coupler configured to provide a variable resistance coupling between the secondary output terminal and the main output terminal to reduce noise at the main output terminal.

Abstract: A RF front-end circuit and a low noise amplifier thereof configured for a receiver are provided. The circuit includes a low noise amplifier and a quadrature passive mixer. The low noise amplifier provides two RF output differential signals to the quadrature passive mixer. The RF signals are down-converted to the differential in-phase baseband signals and the differential quadrature-phase baseband signals. The structure of the RF front-end circuit can avoid the signal and noise interfering between in-phase channel and quadrature-phase channel without using a 25% duty cycle local oscillation generator circuit.

Abstract: A transconductance amplification stage (301) includes a differential pair (306) wherein a bias current flows through each transistor (302, 304) of the pair when input voltages are equal. Tail current boosting circuitry (320), which includes a tail transistor, provides a translinear expansion of tail current of the differential pair. A feedback loop (307) dynamically biases the differential pair to maintain current through one transistor (302) of the pair at the bias current value in spite of a difference between input voltages. Another transistor (304) of the pair provides an output current responsive to a difference between input voltages. The output current is not affected by a region of operation of the tail transistor. An output structure (300, 500) includes the transconductance amplification stage and a circuit (303) for mirroring the output current. An amplifier (800) includes the output structure as a buffer between other structures (801) and an output terminal.

Abstract: An amplifier circuit includes a differential amplifier circuit configured to amplify a voltage between a signal input to a first input terminal and a signal input to a second input terminal, a plurality of output circuits each configured to output a signal corresponding to a signal output from the differential amplifier circuit, and a control circuit configured to set a selected one of the plurality of output circuits in an operating state to drive an output terminal of the selected output circuit, and set a remaining output circuit in a non-operating state and set an output terminal of the remaining output circuit in a high impedance state.

Abstract: In accordance with an embodiment, an audio amplification circuit includes an input stage switchably connected to a switching network through a signal generator and a signal generator stage having a first input and a first output, the first input of the signal generator stage coupled to the first output of the input stage. An output stage is connected to the signal generator stage. In accordance with another embodiment, a method for inhibiting audible transients in an audio signal comprises providing an audio amplification circuit having at least one input and at least one output and coupling a first output to a first source of operating potential in response to one of starting or turning off the audio amplification circuit.

Abstract: A folded cascode operational amplifier includes a constant current source to output a constant current; a differential input stage to output a part of the constant current as a differential current based on a voltage difference between voltages input to an inverting input terminal and a non-inverting input terminal, and connected to the constant current source; and an output stage to output a remaining current obtained by subtracting the differential current from the constant current as an output stage current, and connected parallel to the differential input stage facing the constant current source.

Abstract: A system for signal processing comprising a cyclic analog to digital converter structure having a first stage and a second stage, wherein the first stage is configured to receive an input signal to perform 1.5 bits/stage ADC and to generate a first stage output signal, and the second stage is configured to receive the first stage output signal and to perform fine offset tuning using a final conversion phase. The second stage further configured to perform 1.5 bits/stage ADC and to generate a second stage output that is fed back to the first stage to iteratively generate a next 1.5 bits, until (N?3) most significant bits of N bits of data are generated. A third stage configured to generate a three least significant bits of the N bits of data using a flash ADC sampling circuit that samples a residue signal at the output of the first stage.

Abstract: An envelope detector (ED) includes a voltage-mode ED core including parallel detection transistors for detecting a voltage envelope of a radio frequency (RF) signal input, the RF signal input including an output of a radio such as a cellular transmitter (TX). The ED further includes multiple voltage amplifiers positioned serially in gain stages between the TX output and the ED core to provide a total linear voltage range of the envelope detector. A final voltage amplifier of the multiple voltage amplifiers drives the ED core and includes a class-AB RF amplifier configured to operate within a full linear voltage range of the ED core.

Abstract: An operational amplifier module including an operational amplifier circuit, a rate-increasing circuit and an overdriving circuit is provided. The operational amplifier switches an input voltage to an output voltage and outputs the switched output voltage. The rate-increasing circuit receives the input voltage and the output voltage and increases the rate of switching the input voltage to the output voltage according to the difference between the input voltage and the output voltage. The overdriving circuit provides an overdriving voltage to the rate-increasing circuit and the operational amplifier circuit during an overdriving period according to a selection signal. The level of the overdriving voltage is higher or lower than the levels of the input voltage and the output voltage. Furthermore, a method for increasing the slew rate of the operational amplifier circuit is provided.

Abstract: Amplifiers with voltage and current feedback error correction are provided. In one embodiment, an amplifier includes a first input terminal, a second input terminal, an output terminal, a first stage, and a voltage feedback amplification circuit. The first stage can be used to generate first and second output currents, which can be used to control a voltage level of the output terminal. The first and second output currents can change in response to a current feedback signal and a differential input signal received between the first and second input terminals. The first stage can also generate a voltage feedback signal, which can be used by the voltage feedback amplification circuit to control a voltage level of the second input terminal based on a voltage level of the first input terminal.

Abstract: A power efficient, small-packaged radio frequency (RF) transmitter for use in avionics applications. The RF transmitter utilizes Cartesian feedback to operate a power amplifier with Class AB biasing and efficiency, while delivering Class A biasing performance. The RF transmitter includes interstage pads and high pass filters specially configured to meet demanding requirements for both adjacent channel power (ACP) limits and wideband spurious energy limits. The RF transmitter is much smaller in size and dissipates less DC power and heat than previous RF transmitters used in avionics applications.

Abstract: A decision feedback equalizer is disclosed. The decision feedback equalizer comprises an amplifier circuit and a latch. The amplifier circuit is configured to receive an input signal, a decision feedback signal and a control signal, and is configured to adjust its driving capability according to the decision feedback signal and the control signal to provide an amplified signal of the input signal. The latch is configured to latch the amplified signal as an output signal.